I’m so stressed and tired please help me please with my math homework as fast as possible

Question

Question 1: Identify a possible explicit rule for the nth term of the sequence 5, 3, 1, −1, −3, ….

A.) a_n = 2n + 3

B.) a_n = n + 4

C.) a_n = 7 − 2n

D.) a_n = 2n + 1

Question 2: Identify the 7th term of the geometric sequence in which a2 = 324 and a4 = 36.

A.) 4/3 or −4/3

B.) 1/3 or −1/3

C.) 1/3

D.) 4/3

Answer 1

a(n) = a(1) + (n-1)d

d = -2

a(1) = 5

a(n) = 5 + (n-1) -2

a(n) = 5 - 2n + 2

a(n) = -2n = 7 (c)

a(n) = a(1) *r^(n-1)

here n = 3 and a(1) = 36 and a(n) = 324. Use that to find r:

a(n) = a(1)* r^2

36 = 324 * r^2

1/9 = r^2

1/3 = r

since a(4) = 36 and r = 1/9, a(7), will be 36 * 1/3 * 1/3 * 1/3 = 4/3 (D)