It is eight if u read the last part by the way says so that makes it 8
14)
2(-3)² => 2(-3)(-3) => 2*9 = > 18
27+18-11 => 27 + 7 = > 34.
16)

17)

It's 21 square units. If you map it on a complex plane (x-axis is real numbers, y-axis is imaginary numbers) you'll see that the sides of the rectangle is 3 and 7 which multiply to 21.
R = 960x ft/min
Explaination : 960 is the rate at which the elevator will rise in a minute, while the 'x' represents the amount of minutes passed. Finally the label in the end clarify the units of measure.
greatest common factor=gcf
least common multule=lcm
with 12 and 16
factors of 12=2 times 2 times 3
factors of 16=2 times 2 times 2 times 2
greates common factor is 2 times 2=4
least common multiple means all factors combined minus repeats or 2 times 2 times 2 times 2 time 3=48