Here are the terms:

7, 16, 25, 34, 43, 52, 61, 70, 79

As you can see the pattern here is add 9.

**The 9th term will be 79.**

First one is C

second one is D

their one also D

The principal square root of 8 is a positive quantity.

(principal square root of 8)^2 = 8.

Y is the outside angle to angle Z.

An outside angle is equal to the sum of the two opposite inside angles.

The two opposite inside angles of Y are 42 and 55.

Y = 42 + 55 = **97 degrees.**