PLEASE HELP!!!!!!!!!!!!!!

1)Find the common difference for the given sequence.

1.05, 1.1, 1.15, 1.2, ...

A 0.005
B 0.05
C 0.5

2)Which of the following is an arithmetic sequence?

A 0, 2, 4, 6, ...
B 1, 2, 4, 8, ...
C 1, 4, 8, 13, ...

3)Find the common difference for the sequence shown.

56, 49, 42, 35, ...

A -12
B -7
C 7