2.7^x-1-7^x+2+341=0

Tính hợp lý (nếu có thể)
a) A = (2¹⁷+17²).(9¹⁵ – 3³⁰ ).(2⁴ – 32²)  
b) B =(2⁸.8³) : (2⁵.2³) 
c) C = 64⁴.16⁵ : 4²⁰

Tính hợp lý (nếu có thể)
a) A = 27³.9⁴.(-243)
b) B = 5⁶ :5³ +3³.3² 
c) C = 3¹⁰⁰ – 3⁹⁹ + 3⁹⁸ –...– 3+1 

Ex2: Read following passage and then choose the best answer the each of the questions 

This is my friend. Her name is Linh. She goes to school from Monday to Saturday. Her school is on Le Loi Street and it is big. It has five floors. Linh's classroom is on the third floor. She is in grade 6 class 6A. There are thirty-two pupils in her class.
Linh starts her classes at 2 o'clock in the afternoon and finishes them at 4:30. On Monday, she has Math, Literature and English. After school, Linh plays badminton, but her friend, Lien doesn't play it; she plays volleyball. Linh goes home at 5:30.

When does Linh go to school?

Sunday

From Monday to Sunday

Monday

From Monday to Saturday

Which grade is she in?

6

9

6A

8

How many pupils are there in Linh's class?

13

32

23

30

Does Linh play badminton after school?

No, she doesn't

Yes, she does

Yes, she do

She plays soccer

According to the passage, which of the following is TRUE?

Linh’s school has 3 floors.

Linh’s school has 4 floors.

Linh’s school has 2 floors.

Linh’s school has 5 floors.