---
# System prepended metadata

title: "\U0001F3C5 DAY2 每日任務"
tags: [JS 直播班  - 2021 秋季班]

---

# 🏅 DAY2 每日任務
###### tags: `JS 直播班  - 2021 秋季班`


以下兩題請合併為一份 CodePen 繳交，並透過「註解」進行回答。

問題一
---
以下變數 a, b, c, d, e, f 它們的值、型別各自為何? (請先想想看，不要用 console.log 檢查)

```js=
let a = "10" + "10";
let b = "10" * "10";
let c = 10 + "10";
let d = 10 * "10";
let e = 10 - "2";
let f = "10" - "2";

```

請依照以下格式回答

>問題一
>a = 值, 型別
>b = 值, 型別



問題二
---
請問以下題項哪些是有問題的，並說明為什麼。

```js=
// 1
let myName = "jay";

// 2
var _state = true;

// 3
let true = true;

// 4
const 520Pretty = 520;

// 5
const appleNum = 10;
appleNum = 2;

//6
var ming ='小明';
var ming = '小民';

//7
const ming = '小明'; 
const ming = '小民'; 

//8
let ming = '小明';
let ming = '小民'; 

//9
let ming = '小明';
ming = '小民';

// 10
let $open = "芝麻開門';
```

範例回答格式:
> 問題二
> (2)，因為 blablabla 
> (3)，因為 balabababa 


回報流程
---
將答案寫在 CodePen 並複製 CodePen 連結貼至 thread 中回報就算完成了喔! 解答請參考下圖（需打開程式碼的部分觀看）

![](https://i.imgur.com/6UoJVtD.png)

<!-- 問題一 解答
a = "1010"，string
b = 100，number
c = "1010"，string
d = 100，number
e = 8，number
f = 8，number
-->


<!-- 問題二 解答
(3)，關鍵字不可以用來作為變數名稱
(4)，變數名稱的開頭不可以使用數字
(5)，const 不可以重新被指派值
(7)，因為 const 不可重複宣告，會呈現 Uncaught SyntaxError
(8)，因為 let 不可重複宣告，會呈現 Uncaught SyntaxError
(10)，"芝麻開門' 的分號必須成對
-->

| slackName | codePen 連結 |
|:---------:|:------------:|
| 威廉姆 | https://codepen.io/CodingTrain_1/pen/yLoYOpy |
| sheng wei | https://codepen.io/sheng-wei12/pen/BadyezM |
| Iris Huang      | https://codepen.io/ythuang/pen/MWvYExo                            |
| 陳sam           | https://codepen.io/euldpliv/pen/NWvPaVN                           |
| 喜美            | https://codepen.io/Candace802/pen/dyzPZyr                         |
| POPEYE          | https://codepen.io/popeye_ux/pen/XWaJeOV                          |
| Aaron Tu        | https://codepen.io/aarontu/pen/NWvPaOG                            |
| 彣ㄨㄣˊ         | https://hackmd.io/Er4R-j-ASgeDNAoLUhD2pA                          |
| 咖咖            | https://codepen.io/PlayFunCa/pen/YzxPEXo?editors=0011             |
| Tim Lin         | https://codepen.io/TimmyLin/pen/rNzaYVd                           |
| Genos           | https://codepen.io/pb220416/pen/RwZNjwX                           |
| jojoy           | https://codepen.io/jojoy/pen/LYjEOPM?editors=0010                 |
| 艾瑞克          | https://codepen.io/ericla/pen/NWvPwqR?editors=0010                |
| CloThEs         | https://codepen.io/bogwdnxx-the-sans/pen/GRvgONJ                  |
| Karen Huang     | https://codepen.io/Coding_Snorlax/pen/LYjEObv                     |
| 群嘉            | https://codepen.io/efzdamnp-the-lessful/pen/MWvYOJQ?editors=0010  |
| 米米            | https://codepen.io/Jameshsu0407/pen/PoKwOwq?editors=0011          |
| lumei           | https://codepen.io/l_umei/pen/jOLEamL?editors=0010                |
| 凱文            | https://codepen.io/KevinHaHa/pen/jOLEawG                          |
| Cheng Pei-hsuan | https://codepen.io/PaCheng/pen/wvqBPJo                            |
| Jun Ting Lin    | https://codepen.io/jake1155/pen/KKvwyzq                           |
| YuriT           | https://codepen.io/wenfisht/pen/MWvYOEG?editors=0010              |
| Kelvin Hsu      | https://codepen.io/kelvin001/pen/qBXEVpG?editors=1010             |
| Arista          | https://codepen.io/arista-hsieh/pen/GRvgOQZ?editors=1010          |
| Andy Huang      | https://codepen.io/HsuHuaHuang/pen/BadymYp                        |
| kevinhes        | https://codepen.io/kevinhes/pen/JjyoOOV?editors=0011              |
| 林小君          | https://codepen.io/hcvbcjqq-the-vuer/pen/MWvYOLP                  |
| ボンドルド      | https://codepen.io/alan60108/pen/qBXEVrv                          |
| Jessie          | https://codepen.io/jssanji03/pen/VwzYraJ?editors=1010             |
| Sunny           | https://codepen.io/shihchinghuang/pen/KKvwyLe                     |
| Sharon Chang    | https://codepen.io/npxuxgef/pen/porvdOV                           |
| Bonnie          | https://codepen.io/bonnieli1414/pen/ExvaoKY                       |
| Joy Cheng       | https://codepen.io/joycheng5432/pen/WNEbdez?editors=0011          |
| AKI             | https://codepen.io/akichen27/pen/xxLbpRG                          |
| 連小艾          | https://codepen.io/bolaslien/pen/VwzYyaK?editors=0010             |
| Cadiis          | https://codepen.io/candiyen/pen/dyzPJOp                           |
| Lai             | https://codepen.io/co_lai/pen/KKvwZyE                             |
| Ka              | https://codepen.io/potatokaka/pen/RwZNxoV                         |
| Elaine Liu      | https://codepen.io/elaine7598/pen/porvpwY?editors=1010            |
| Peter Chen      | https://codepen.io/yuckugjy-the-sasster/pen/RwZNxyj               |
| Peggy Tsai      | https://codepen.io/pei-chi-tsai/pen/VwzYyzp?editors=0011          |
| 洋蔥            | https://codepen.io/oikdkmxq-the-looper/pen/WNEbdJL?editors=0010   |
| Sam             | https://codepen.io/sam-hsu/pen/BadyJqO                            |
| Yunei           | https://codepen.io/Yunei/pen/eYEmyap                              |
| Beanhuang       | https://codepen.io/Beanhuang/pen/rNzapgx?editors=0110             |
| YC Lu           | https://codepen.io/YCLu/pen/ExvaQmX                               |
| Metis Teng      | https://codepen.io/metis-teng/pen/KKvwQMw?editors=0011            |
| Yumi            | https://codepen.io/chenhsiuju/pen/bGrNLMN                         |
| phiphiphi27     | https://codepen.io/aiya861202/pen/eYEmVjR                         |
| Jasper          | https://codepen.io/li-jasper/pen/dyzPdgg?editors=0010             |
| 雪莉            | https://codepen.io/utshang216/pen/RwZNQVe                         |
| Bella Shya      | https://codepen.io/BellaXie/pen/YzxPePa?editors=0010              |
| Jocelyn         | https://codepen.io/enjoyful/pen/BadyYeN?editors=0010              |
| LeoChen         | https://codepen.io/leo-chen/pen/QWMwQzE                           |
| Sylvia-H        | https://codepen.io/Cosmosheart/pen/zYdxRgW?editors=0011           |
| Riley           | https://codepen.io/jjpxbprd/pen/porvLgr                           |
| Shiny           | https://codepen.io/shinychen/pen/ZEJYvag                          |
| Anna            | https://codepen.io/kycrleao/pen/MWvYVpQ?editors=0011              |
| Gill            | https://codepen.io/Gill-Chin/pen/XWaJEKY?editors=0011             |
| LTL             | https://codepen.io/ltlin93/pen/abyzYda?editors=0010               |
| 鄭安志          | https://codepen.io/lwmtsgek/pen/zYdxjzY?editors=0011              |
| 劉維倫          | https://codepen.io/lun0223/pen/GRvgdrv                            |
| Yashien Lin     | https://codepen.io/YashienLin/pen/bGrNMwM?editors=0011            |
| Phil            | https://codepen.io/ctkeftjp-the-animator/pen/NWvPMeo?editors=0010 |
| Pei Ying        | https://codepen.io/Pei-Ying/pen/OJjPZmQ?editors=0011              |
| Van.S.          | https://codepen.io/fbacojji-the-selector/pen/eYEmrwp              |
| Booker          | https://codepen.io/bookbasketball/pen/YzxPvNv                     |
| IvyHe           | https://codepen.io/j06ivy/pen/vYJErXa?editors=0010                |
| 蔡明達          | https://codepen.io/bmzpfyxe/pen/NWgKQZB?editors=0011              |
| 溫溫            | https://codepen.io/ZPXO1928/pen/yLoyqRE                           |
| Gui             | https://codepen.io/guitimliu/pen/gOxbjvM                          |
| RainLiao        | https://codepen.io/billpop741/pen/QWMwxrj                         |
| Fleur           | https://codepen.io/swwlee/pen/KKqjvYv                             |
| 陳暐中          | https://codepen.io/wei-z/pen/gOxbdev?editors=1111                 |
| 張喆            | https://codepen.io/wow767t/pen/yLoyxWB                            |
| Hsiang          | https://codepen.io/chao20211/pen/NWvPXxM?editors=0010             |
| Aya             | https://codepen.io/NoNameNote/pen/JjyomLp                         |
| YU              | https://codepen.io/vickyj304/pen/porvxMe?editors=0011             |
| Trista          | https://codepen.io/trista6140/pen/yLoyQNX                         |
| ZY Hsu          | https://codepen.io/zihyin/pen/OJjPaoW?editors=1010                |
| PageShih        | https://codepen.io/kanawin821/pen/jOLEQRz?editors=0010            |
| 吉兒            | https://codepen.io/Jillkate/pen/abyzRyy                           |
| Yunyi           | https://codepen.io/yunyi12374/pen/YzQojyV                         |
| Leo             | https://codepen.io/cdjhs310174/pen/eYEmbrO?editors=0010           |
| Peter           | https://codepen.io/shiou-ho/pen/RwZNEvx                           |
| Jeff            | https://codepen.io/jeff-cheng/pen/RwZNvbM                         |
| lingxuan        | https://codepen.io/penglingxuan/pen/xxLbMwd                       |
| 啊和            | https://codepen.io/shnny/pen/wvqBYOa?editors=0011                 |
| Vicky Kao       | https://codepen.io/vicky03035/pen/XWaJOmj                         |
| 格可            | https://codepen.io/catabo/pen/mdMyvyK                             |
| Jean Chiang     | https://codepen.io/jeanchiang1221/pen/RwZNvXm                     |
| jian hao wong   | https://codepen.io/jianhao215/pen/jOLEdXr                         |
| 黃士桓          | https://codepen.io/shr-huan-huang/pen/porvYvP?editors=0010        |
| Juno Li         | https://codepen.io/Juno026/pen/XWaJORp?editors=0011               |
| 乃萱         | https://codepen.io/nainaikuo/pen/MWvYxJr?editors=0011               |
|Mizu    | https://codepen.io/mizu-yang/pen/JjyozJx?editors=1010 |
| UnizaLin | https://codepen.io/unizalin/pen/GRvgeEJ |
|Steven Chan |https://codepen.io/Steven1220/pen/eYEmLRw?editors=1010 |
|Sandy|https://codepen.io/Sandy_L/pen/KKvwrOe?editors=0011|
| pei | https://codepen.io/z-pei/pen/Jjyoxxv?editors=1111 |
| Jyun Chen | https://codepen.io/Jyun_C/pen/PoKwLQz?editors=
| 小紹 | https://codepen.io/shaoci/pen/mdMyQeb
| 小K | https://codepen.io/kelen1995/pen/KKvwEMm
| Celeste | https://codepen.io/Celeste17/pen/gOxbyrR|
| Tingyu | https://codepen.io/dgltu/pen/eYEmmJw?editors=0010 |
| VerienLu | https://codepen.io/verien/pen/PoKwgvB |
| debby yeh| https://codepen.io/bhliyoup/pen/eYEmagz|
| TsungHsien | https://codepen.io/cykczxev-the-sasster/pen/bGrNZqB |
| YU-LING TUNG | https://codepen.io/igzdflpu/pen/JjyoqgB?editors=0010 |
| 傅劍軒 | https://codepen.io/seonkuraito/pen/zYdxQad?editors=0010 |
paul| https://codepen.io/printfootya/pen/KKvwjdW?editors=0011
Hamaji|https://codepen.io/hamajibashi/pen/XWaJwOe
fyfy|https://codepen.io/fyfy1217/pen/wvqBLzG?editors=0010 |
Zooey Cheng|https://codepen.io/noraneko0430/pen/WNEbqdj?editors=0012|
| danny123      | https://codepen.io/binlandz123/pen/YzxPojP?editors=0010            |     |     |
| wlc           | https://codepen.io/arxmyifs/pen/wvqBbGO?editors=1010               |     |     |
| 小不          | https://codepen.io/SharonWu1987/pen/RwZNXgV                        |     |     |
| homerWu       | https://codepen.io/wuhomer7766/pen/rNzVNwv?editors=0012            |     |     |
| Shaun43       | https://codepen.io/i418063/pen/OJjVMEv                             |     |     |
| Hua樺         | https://codepen.io/yivava/pen/QWMbEqv                              |     |     |
| Ellen Chen    | https://codepen.io/ellenchialin/pen/oNeXLoO                        |     |     |
| Alvin         | https://codepen.io/Alvin20201116/pen/wvqazBq                       |     |     |
| 吐司          | https://codepen.io/malolulu/pen/porJErQ                            |     |     |
| 劉毓哲        | https://codepen.io/JERO0729/pen/zYdGNOp?editors=0010               |     |     |
| Irene Wang    | https://codepen.io/irene-wang-the-looper/pen/RwZPKaz               |     |     |
| 傑瑞          | https://codepen.io/auatwood909815/pen/gOxpLzq?editors=0012         |     |     |
| Bob_Lai       | https://codepen.io/yameday/pen/WNEvRqX                             |     |     |
| Jie Du        | https://codepen.io/qgqonost-the-flexboxer/pen/PoKqWOZ?editors=0010 |     |     |
| 許閔翔        | https://codepen.io/oupbzfxq-the-scripter/pen/RwZPpOj               |     |     |
| Meng          | https://codepen.io/MGHN/pen/jOLPBzQ?editors=0012                   |     |     |
| Kin Hei Shing | https://codepen.io/kinhei-shing/pen/bGrdrqL?editors=0012           |     |     |
| 柯勝華        | https://codepen.io/Chill-Nick/pen/VwzLrRw?editors=0011             |     |     |
| Yvonne        | https://codepen.io/Evonne/pen/gOxpoYL?editors=1010                 |     |     |
| Louis         | https://codepen.io/Louis164156/pen/PoKqRMb                         |     |     |
| Eva Lo        | https://codepen.io/hsiaoi/pen/GRvJdNr?editors=0011                 |     |     |
| ZOE WU        | https://codepen.io/Zoechiueh/pen/WNEvJrd?editors=0011              |     |     |
| 肉魚          | https://codepen.io/zoechen13/pen/wvqaEbx?editors=0010              |     |     |
| Ching         | https://codepen.io/Jaimedede/pen/KKvpjEX                           |     |     |
| 陳品宏        | https://codepen.io/wtka/pen/porjbVw                                |     |     |
| 大衛          | https://codepen.io/exnsrpjc/pen/GRvpZKO?editors=0010               |     |     |
| Kailun        | https://codepen.io/Kailun/pen/gOxamPM                              |     |     |
| 小木馬        | https://codepen.io/wmmtbcsd/pen/OJjygpL                            |     |     |
| Jun Hua       | https://codepen.io/ydsyvkph/pen/eYEpRQV                            |     |     |
| Ralph Tseng   | https://codepen.io/Ralph19/pen/yLoYvQN                             |     |     |
| GrayShine  | https://codepen.io/grayshine/pen/eYEpjWR?editors=0010                 |     |     |
| 阿修  | https://codepen.io/edw-kyo/pen/vYJNzRK?editors=0010                 |     |     |
| Tina |          https://codepen.io/Tina0721/pen/LYjpqxb                            |     |     |
|natsu|https://codepen.io/natsu19/pen/KKvdJJK?editors=0010|
| zyc       | https://codepen.io/zy_c/pen/MWvadzw?editors=0010                                   |
| Nina       | https://codepen.io/NinaYYX/pen/XWamvay |
| 鉦勝       | https://codepen.io/atckmax823/pen/OJjNWVB?editors=0010 |
| Huan Pei       |https://codepen.io/patrickrrr007/pen/WNEwyzK?editors=0010 |
| Alberto       |https://codepen.io/AlbertoLL/pen/eYEzdmv?editors=0010 |
|tomatohuang|https://codepen.io/shellyhwung/pen/PoKzdRo|
|Sihle Huang|https://codepen.io/bugbug777/pen/YzxWdwO?editors=0011|
|YJ kung| https://codepen.io/bagelover/pen/vYJKmom?editors=0010 |
|施宇|https://codepen.io/ItsMeRain/pen/QWMdemP?editors=0011|
|Calon|https://codepen.io/Calon0118/pen/wvqJOEd?editors=1010|
|zaii|https://codepen.io/ivy2846357/pen/BadqyKj?editors=0010|