Giúp mình ,mình đang cần gấp
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(n_{Fe_3O_4}=\dfrac{8}{232}=\dfrac{1}{29}\left(mol\right)\)
\(Fe_3O_4+8HCl\rightarrow FeCl_2+2FeCl_3+4H_2O\)
\(\dfrac{1}{29}.......\dfrac{8}{29}................\dfrac{2}{29}\)
\(m_{HCl}=\dfrac{8}{29}\cdot36.5=10.06\left(g\right)\)
\(m_{FeCl_3}=\dfrac{2}{29}\cdot162.5=11.21\left(g\right)\)
ờ...tớ ko nhầm thì thừa are
nếu bỏ are thì she's making a papper boat
a) \(\dfrac{3}{4}+\dfrac{9}{5}\div\dfrac{3}{2}-1=\dfrac{3}{4}+\dfrac{18}{15}-1=\dfrac{39}{20}-1=\dfrac{19}{20}\)
b) \(\dfrac{6}{7}\cdot\dfrac{8}{13}+\dfrac{6}{13}\cdot\dfrac{9}{7}-\dfrac{4}{13}\cdot\dfrac{6}{7}=\dfrac{48}{91}+\dfrac{54}{91}-\dfrac{24}{91}=\dfrac{48+51-24}{91}=\dfrac{78}{91}=\dfrac{6}{7}\)
c) \(\dfrac{-3}{7}+\left(\dfrac{3}{-7}-\dfrac{3}{-5}\right)\)\(=\dfrac{-3}{7}+\left(\dfrac{-3}{7}-\dfrac{-3}{5}\right)=\dfrac{-3}{7}+\dfrac{6}{35}=-\dfrac{9}{35}\)
a: Xét tứ giác AEHF có
\(\widehat{AEH}=\widehat{AFH}=\widehat{FAE}=90^0\)
Do đó: AEHF là hình chữ nhật
1 How long do you live in HN
2 How often did you go to the movies
3 What did Mrs Robinson buy
4 When was your father in Nghe An
5 How do they go to school
6 Why didn't she go to class
7 Who left home at 7o'clock yesterday
8 What subject does he study in the high school
9 What is your favorite hobby
10 How far is it
\(a, 48.19+81.48\)
\(=49.(19+81)\)
\(=49.100=4900\)
\(b,23.134-34.23\)
\(=23.(134-34)\)
\(=23.100=2300\)
3 C
4 B
5 A
6 B
7 A
8 A
9 C
10 D
11 B
12 B
13 A
14 C
15 B
16 A
17 D
18 D
19 C
20 A
21 B
22 B
23 C
24 D
25 B
26 D
27 A
28 D
29 C
30 B
31 C
32 A
33 A
Viết lại câu
12
Authorities in Ho Chi Minh City suggested that current school break schould be extended by us until the end of March to control the epidemic caused by Covid-19
15 The plumber who has just been had check the pipes in my house is very skillful
16 In spite of the fact that we had invited her to the party, she didn't come
17 Since they didn't have a map, they lost their way
18 I suggest that energy-saving bulbs should be used to reduce the electricity bill
19 We are looking forward to seeing your gook action from your company
20 Linda congratulated Owen on scoring a wonderful goal
21 She had all the water pipes in her house checked by the plumber yesterday
22 If you go on smoking, you will be seriously sick
23 I suggested all the bag should be collected and taken to the garbage dump
24 If you aren't carefull, you will fall over the rocks
25 If you work too much, you will feel tired
26 If you are careless, you'll break the vase
4c
5a
6b
câu 10
tổ 1 trồng số cây là
8x12=96 cây
tổ 3 trồng số cây là
80+14=94 cây
trung bình mỗi tổ trồng số cây là
(96+80+94):3=90 cây