Answer:
0.508 cm
Step-by-step explanation:
Your problem statement tells you that you can find the number of centimeters by multiplying 1/5 inch by 2.54 cm/in:
1/5 × 2.54 = 0.508
1/5 inch is 0.508 centimeters
The recursive formula 
means that the next term in the sequence is 5 more than the previous one.
So, we know that we start from 
, which means that the next term is
Similarly,
Answer:
(b) a perfect cube
Explination:
It is a perfect cube of 5
First add 7d to both sides:
-22 = 11d
Now divide by 11 both sides
-2 = d
You can work on either side of the equation, I used the right side for the variables because it was easier to add to positive numbers than dealing with negative numbers on the left side:
-7d -4d = 22
-11d =22
d = -2
either way you get the same answer :)
