a. Vì bóng đèn mắc nối tiếp nên cđdđ I1, I2:

I = I1 = I2 = 0,2A

b. HĐT U2 giữa hai đầu bóng đèn Đ2:

U2 = U - U1 = 6 - 2,5 = 3,5V 

1, chỉ cách làm mẫu nek:

NO+O2=>NO2

NO+O2 là vế 1, NO2 là vế 2

vế 1 : N=1, O=3 

vế 2 : N=1, O=2

cân bằng: 

vế 2: 2O2( O vế 2 ít ng tử hơn ) 

lúc này vế 2 có O=4  vàN=2

vế 1: 2NO 

lúc này vế 1 N=2, O=4

kl : 2NO+O2=>2NO2

2 , làm y như nãy:

4P+5O2=>2P2O5

3, Fe2O3+3H2SO4=>Fe(SO4)3+3H2O

Noise pollution is any loud sound that is either harmful or annoying to humans and animals. Generally, noise is produced by household appliances, big trucks, vehicles and motorbikes on the road, as well as planes and helicopters flying over cities, and loudspeakers. Noise pollution can cause stress, illnesses, hearing loss, sleep loss, and lost productivity. Its health effects include anxiety, stress, headaches, irritability, and nervousness. Therefore, noise-producing industries, airports, and bus terminals should be located far from living areas. Moreover, officials should check the misuse of loudspeakers, outdoor parties, discos, and public announcement systems. By doing so, we can reduce noise pollution and protect people’s health

D

d

Khổ thân :)

khổ vậy, khổ thân, học, học nữa, học mãi

1 If you are Vietnamese, you should know the story of Chung cakes and Day cakes

2 What leisure activity o you think is the best for teenagers?

3 People in rural areas often talk more optimistically about the future than city people

4 Do we have to follow the tradition of cleaning the house before Tet

5 Unlike many other jobs, farmers depend heavily on the weather

6 Medical help can be obtained more easily in a city than in the countryside

7 In our country, it is against the law to discriminate against any ethnic or religious group

8 What are the benefits of using computers or mobile phones for leisure activities?

9 In Viet Nam, you should wait for the eldest person before you sit down

10 Many ethnic groups have their own languages, and some even have written languages

1.If you are Vietnamese,you should know the story of chung cakes and day cakes.

2.what leisure activity do you think is the best for teenagers?

3.People in the rural areas of Britain talk about the future more optimistically than city people.

4.Do we have to follow the tradition of cleaning the house before Tet.

5.Unlike many jobs,farmers depend heavily on the weather.

- mất mùa

- thiệt hại về kinh tế

- thiệt hại về con người

- Thiệt hại về nhà cửa, các cửa hàng nhỏ...

mất mùa

- thiệt hại về kinh tế

- thiệt hại về con người

- Thiệt hại về nhà cửa, các cửa hàng nhỏ...

children là số nhiều đi với have

còn nếu là child thì là số ít đi vs has nha

còn 1 số từ gần giống vs children : 

man-men

woman-women

tooth-teeth

foot-feet

mouse-mice

.....

khá nhiều , bn tra trên gg là ra đó!

\(3x=1\)

\(x=\dfrac{1}{3}\)

3x-1=0
3x=0+1
3x=1
x=1:3
x=1/3
Vậy x=1/3