Answer:
4
Step-by-step explanation:
a^3 = 64
therefore , a = 4
the angle 4pi/5 in quadrent 2
X=

Or it would be approximately: x≈ 0.37228132, -5.37228132
Hope this helped! ;P

(prounounced "y bar") is the mean of the y values
Add up the y values to get
5+7+10+15+18 = 55
Then divide by 5 (because there are five y values) to get
55/5 = 11
Therefore,

The answer is choice C