Cho đa thức A(x)=Ax³+Bx²+cx+D

Biết Ax luôn chia hết cho 5 với mọi x thuộc z.

C/M:ABCD cũng chia hết cho 5

Thực hiện các phương trình phản ứng hóa học sau và ghi rõ điều kiện phản ứng(nếu có)

1.H2SO4+Al→

2.H2SO4+Mn→

3.H3PO4+Cu→

4.H3PO4+Mg→

5.H3PO4+Fe→

6.H3PO4+Zn→

7.H3PO4+Al→

Thực hiện các phương trình phản ứng hóa học sau và ghi rõ điều kiện phản ứng(nếu có)

1.HCl+Cu→

2.HCl+Ag→

3.HCl+Fe→

4,HCl+Zn→

5.HCl+Mg→

6.HCl+Al→

7.H2SO4+Cu→

8.H2SO4+Mg→

9.H2SO4+Fe→

10.H2SO4+Zn→

1.The mobile phone is the most popular means of...................(communicate)

2.We're......................on collecting stamps(hook)

3.He used to be...................the internet,but now he isn't(addict)

4.You have to use your...................to read books(imagine)

5.She felt.....................with the result os her examination(satisfy)

6.You can do.....................activities in your free time(relax)

7.The boy was..............................about the trip(excite)

8.Using the computer too much is........................to your eyes(harm)

9.It's an extremely....................cure for a headache(affect)

10.Their...........................was great.Every one enjoyed it(perform)

Cho tam giác ABC vuông tại A , M là trung điểm của BC . Lấy điểm D thuộc cạnh BC . H và I thứ tự là hình chiếu của B và C xuống đường thẳng AD .Đường thẳng AM cắt CI tại N.C/M

a) BH = AI

b)DN vuông với AC

c)BH2+CI2 ko đổi D thay đổi trên cạnh BC

Giúp mình

0.We started living here fifteen years ago

→We have...................................................

1.The last time she visited me was at my wedding

→She hasn't...........................................

2.I last wrote to my uncle in July

→I haven't.................................

3.It's a long time since we became close friends

→We have..............................................

4.Minh began to collect stamps in 2000

→Minh has.....................................................

5.I last called her up 2 days ago

→I haven't................................................

6.Did you finish the test an hour ago?

→I haven't.........................................................

7.I started playing tennis last year

→I've................................................

8.I have never read such a romantic story

This is...........................................

1.This is first time I have listened to this song

→I have never.......................................

2.He has never played a computer game before

→This is....................................................

3.She has never opened an bank account before

→This is...................................................

4.This is the best film I've ever seen

→I've...................................................................

1.My teacher hasn't given us any tests for 1 month

→It's.........................................................

2.It's ages since I saw her

→I haven't...................................................

3.Is's a long time since we became close friends

→We have..............................................

4.It's three years since he last came here

→He hasn't.......................................................

5.They haven't written to each other for years

→It's years..........................................................

1.The last time he met her was on Cheistmas day

→He has not.......................................

2.They haven't talked to each other for 2 months

→The last time................................................

3.I haven't played badminton for a week

→I last...........................................

4.The last time I played tennis was in 1990

→I haven't ..............................................

5.She last visited me was five months ago

→She hasn't...................................................

1.They started cooking 30 minutes ago

→They've..................................................

2.I have studied English for three years.

→I began.....................................................

3.He began working here since 2011

→He has...........................................................

4.When did you begin to live here?

→How long....................................................................

5.How long have you played football?

→When.................................................................?