Answer:
A) 10.00
Step-by-step explanation:
10.00 x 0.8 is equal to 8 giving a total of 18.00. But it is incorrectly done in the table.
I=√-1 and all the steps are there
Try 18mm that should be the answer
Note that

and

.
From the unit circle, we can check that

and

have the same value, but opposite signs, that is:

.
Thus,

.
Note that

is the x-coordinate of the lowest point on the unit circle, that is (0, -1). Thus

Answer: 0