Task 13

1 D

2 C

Task 14

1 - B

2 - D

Task 15

1 B

1. B

2. C

b c

 1B

2C

1,B

2,D

3,D

4,A

1,B

2,A

3,C

4,D

Task 15

1 B

2 D

3 A

4 A

Task 16

1 B

2 A

3 C

4 D

b d a a b a c d

1 C

2 C

A-C

c c

Theo giả thiết, ta có:

\left( {\widehat {SC,\left( {ABC} \right)}} \right) = \widehat {SCA} = {30^^\circ } \Rightarrow SA = AC\tan {30^^\circ } = \frac{{a\sqrt 3 }}{3}

Vậy thể tích khối chóp S.ABC là:

kb nha!

kb ko mình luôn chào đón

wow,bạn lễ phép ghê,biết là mik vi phạm nên xl cũng tốt havậy cứ kb với mik nha

C

ko biết :v

C

B

C

B

chắc A

The com pany is going to close....................one of it s stores due tore duced sales.

A.on                     B.to                      C.down

23.He was think in go fo passing....................the work shop to his es destson.

A.with                  B.to                      C.down

24.You had to face up....................the fact that she would never come back.

A.to                      B.at                      C.with

25.I just won dered why she turned....................his offerofhelp.

A.on                     B.down                C.back

26.He is going to set....................a travel company nex tyear.

A.down                B.with                  C.up

27.If she doesn’t turn....................bye.15 they will leave the party.

A.on                     B.up                     C.off

28.He wan ted someone to take....................his role once here tired.

A.over                  B.up                     C.back

 23.B

laugh - laughed

be - was , were

iump - jumped

ride - rode

Nếu ko hiểu thì hỏi mik nha  mình trình bày hơi khó hiểu