Hòa tan hết 3,1 gam Na2O vào 46,9 gam nước thu được dung dịch A . Tìm C% của chất có trong dung dịch A

E= (3a+b)b sử dụng Bất Đẳng Thức Cô si Giúp e với ạ

mầm ey thiết kế cho wacom một kiểu => ê đẹp không

191. Who is this lady? She (move)…………… into No 4 last month. 192. This hotel is empty, it (not live)……………. in for a long time. 193. What a pity! We‟ve got a bottle of wine but we ( not bring)………….. a corkscrew. 194. They were very busy because a water pipe (leak) ………….. . 195. He (can not)……………. get the lid off so he lost his temper. 196. Yesterday afternoon he (have)…………… a nap in the garden chair when a boy dropped a ball on his head. 197. It was her birthday so he (buy)…………… her a bunch of flowers. 198. He was looking at a map so he (not notice)………….that the car in front of him had stopped at the traffic lights. 199. He was running fast and he (bump)…………….. into an absent-minded old man. 200. We didn’t do the shopping because we (not have) ………….. time.

Bài 1: Tìm 2 số có tổng 1149, biết rằng nếu giữ nguyên số lớn và gấp số bé lên 3 lần thì được tổng mới bằng 2061

Nhanh nha mn ai nhanh ch hay nhất

Vẽ đậu mầm ôm ngực trái (kiểu đau tim í) NL: toy giống cái đề rồi TvT Đau lòng :<

260. Dick ………..(start) school before he ………. (be) seven. 261. You …………. (feel) better after you have something to eat. 262. Susan ……….. (play) chess when she was a child. 263. Our teacher ……….. (tell) us yesterday that he ……….. (visit) England in 1970. 264. He felt asleep while he ………… (do) his homework. 265. You ………… (not know) the value of health until you ………. (lose) it. 266. Our friends asked us why we ………… (come) there so early. 267. While I was writing a letter, the children ………... (play) outside. 268. We ………… (not receive) any letter from him since he………….. (leave) 4 months ago. 269. After my sister ………… (wash) her clothes she began to study. 270. We had hardly begun our walk when it ………. (begin) to rain. 271. They …….. (come) with us as soon as thy finish work. 272. My grandmother ………. (die) after she………. (be) ill a long time. 273. How long you ……………(study) in this school? 274. I ……… (study) here for 2 years. When I ……… (finish) the 5th year, I …………(be) able to get a diploma.

Dùng khí hiđro để khử hoàn toàn 20,25g kẽm oxit ở nhiệt độ cao. a) Hãy viết phương trình phản ứng xảy ra. b) Tính khối lượng kẽm sinh ra sau khi phản ứng kết thúc. c) Nếu thả lượng kẽm trên vào một dung dịch có chứa 7,3 axit clohiđric. Tính khối lượng muối tạo thành.

Giúp mk vs các bn Mk đang cần gấp