Afree-falling object increases speed by a little over 22 miles per hour each second. the arithmetic sequence 22 44 66 represents speed after each second, in miles per hour of a dropped object. how fast is a rock falling after 8 seconds if it is dropped over the side of the cliff?

176 mph after 8 seconds

Step-by-step explanation:

This is an arithmetic sequence with common difference 22 mph and first term 22.  Thus, the nth term is a(n) = 22 + 22(n - 1).

Thus, the 8th term is a(8) = 22 + 22(7) = 176 mph

Step-by-step explanation:

Givens

After 8 seconds refers to the term number eight in the sequence, where the increasing difference is 22 miles per hour. So, the sequence until the second 8 is

Therefore, in the second number 8, the speed is 176 miles per hour, becuase it increases 22 miles per hour each second.

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads