Answer:
1386
Step-by-step explanation:
If you have trouble with that, you can multiply 66 by 20, then 66*1, and add them (break apart the 21.)
Answer:
y*y*y*y*y*y
Step-by-step explanation:

Answer:
90 feet
Step-by-step explanation:
320 (1/8) = 40
3/4 (40) = 30 yards
1 yard = 3 feet
30 (3) = 90 feet
Since it is a rectangular prism, the front and back are the same. the sides are the same and the top and bottom are the same. You would find the area of the front and back first. Since they both have the same measurements, you can find the area of one of the faces and multiply by 2.
A=BH
A= 3x5
A=15
15x2=30
So the front and back's area is 30. Now you find the area of both sides. They are both rectangle so the formula is A=BH.
A=BH
A=3x5
A=15
15x2=30
Now you find the area of the top and bottom. It is also a rectangle so you will use the same formula.
A=BH
A=3x3
A=9
9x2=18
Finally, you add all these measurements together adn that is the surface area.
This surface area of this rectangle prism is 78.