To solve this question, use the Cube surface area formula
Area = 6a^2 in which a = edge.
edge = 8.5
Area = 6(8.5)²
Simplify. Follow PEMDAS
Area = 6(72.25)
Area = 433.5
(C) 433.5 in² is your answer
hope this helps
Assuming a normal distribution we find the standardized z scores for a:-
z1 = (80 - 180) / 25 = = -100/25 = -4
z2 = (280-180) / 25 = 4
Required P( -4 < z < 4) from the tables is >99.9%
b
z1 = 130-180 / 25 = -2
z2 = 230-180 / 25 = 2
from tables probability is 2* 0.4773 = 95.46 %
12 and 3/8 or if you want it entirely in a fraction 99/8.