Yes it is a rational number
7). C
8). 60
n = 5(10) + 10
n = 50 + 10
n = 60
9). 17
f(x) = -2x + 7 plug the -5 in for x
f(x) = -2(-5) + 7
= 10 + 7
= 17
10).
If she has finished 20%, she still has 80% to do. So just calculate .8 times 150.
Here, √x = 0.5
Squaring on both sides,
(√x)² = (0.5)²
x = 0.25
In short, Your Answer would be Option C
Hope this helps!