12 pts; if it's right i promise brainlist; 5-stars; ; beleive me it's simple i

1. find the next three terms in the sequence.
3, 12, 21, 30, . .

a. 40, 50, 60
b. 38, 46, 54
c. 39, 48, 57
d. 36, 32, 39

2. identify the sequence as arithmetic, geometric, or neither.
1.6, 0.8, 0.4, 0.2, . .

a. arithmetic
b. geometric
c. neither

3. 5 • 3n
a. 15, 30, 45, 60
b. 5, 15, 45, 135
c. 0, 15, 45, 135
d. 15, 45, 135, 405

4. use the function rule ƒ(x) = x • |–1|x. find the output ƒ(2).
a. 4
b. 3
c. –2
d. 2