A.Na.
B.K.
C.Ba.
D.Ca.

A.5
B.3
C.2
D.4

A.tính oxi hóa.
B.tính nhận electron.
C.tính khử.
D.tính bị khử.

A.chắc chắn phải có các nguyên tố C, H và N.
B.chỉ có các nguyên tố C, H.
C.chắc chắn phải có các nguyên tố C, H có thể có O, N.
D.chắc chắn phải có đủ các nguyên tố C, H, O và N.

A.C3H9N.
B.C3H7N.
C.C3H8N.
D.C6H18N.

A.C2H2.
B.C4H10.
C.C2H5OH.
D.C4H6.

A.
B.
C.
D.

A.Having conquered everything, the robots have humans do low-skilled physical and highly skilled complex mental jobs.
B.Humans will do low-skilled physical and highly skilled mental job after having the robots conquer everything.
C.Letting the robots conquer everything, humans will have to do low-skilled physical and highly skilled mental jobs.
D.Before doing low-skilled physical and highly skilled complex mental jobs, humans have the robots conquer everything else.

A.Problems in which rules do not currently exist cannot be solved by computers.
B.People cannot solve computers problems in which rules do not currently exist.
C.Problems in which rules do not currently exist have to be solved by computers.
D.People have to solve problems in which rules do not currently exist by computers.

A.I need to clean my shoes.
B.I have to clean my shoes.
C.Cleaning is needed for my shoes.
D.I need to have my shoes cleaned.