Answer:
option D is true.
Step-by-step explanation:
Given the sequence
7, 12, 17, 22, ...
An arithmetic sequence has a constant difference 'd' and is defined by

Computing the differences of all the adjacent terms

The difference between all the adjacent terms is the same
so

as

Thus, the nth term of the arithmetic sequence will be:


Therefore, option D is true.
14). (Take π value as 22/7)
circumference = 66in
2πr = 66in
2×22/7×r = 66
r = 66×7/2×22
r = 21/2in
d = 2r => d = 2×21/2
therefore diameter of the circle = 21in
15). (Take π value as 3.14)
Circumference = 3.14m
2πr = 3.14m
2×3.14×r = 3.14
r = 3.14/3.14×2
r = 1/2m
Therefore the radius of the circle = 0.5m
16). (Take π value as 22/7)
Circumference = 33km
2πr = 33km
2×22/7×r = 33
r = 33×7/2×22
r = 21/4
d = 2r
d = 2×21/4
d = 21/2km
Therefore the diameter of the circle = 10.5km
The answer to the second one is 243/2 but I'm not 100% positive