(A) a triangle whose angles each measure less than 90°
Composite numbers are numbers that have more than 2 factors. With that being said, your answer would be 2.
4 is a composite number: 1, 2, 4
6 is a composite number: 1, 2, 3, 6
8 is a composite number: 1, 2, 4, 8
2 is a prime number: 1 and 2
2 is a prime number, not a composite number.
The surface area (SA) of a cube can be written as:
SA = 6s²
From here we can write, the length of the side s as:

For cube with surface area of 1200 square inches, the side length will be:

inches
For cube with surface area 768 square inches, the side length will be:

inches
The difference in side lengths of two cubes will be:
Rounding to nearest tenth of an integer, the difference between the side lengths of two cubes will be 2.8 inches.
The answer is b 5x-y=7 2x+y=0