1)we calculate the volume of the right rectangular prism
volume=lenght x width x heigth
volume=12 ft * 8.5 ft * 4 ft=408 ft³
density= mass / volume ⇒ mass=volume * density.
density=0.25 pound /ft³
2) we calculate the mass of the right rectangular prism.
mass=volume * density
mass=408 ft³(0.25 pound / ft³)=102 pounds.
answer: c. 102
Hello there!
According to the chart, you can see that for every lawn Nina mows, she earns $15. So it's increasing by 15 per yard.
Let's see if this will help:
1 yard= $15
6 yards = ???
I don't want to give you the answer right away, since I want you to learn how to do it. :)
I hope my hint helped!!
(If you're really stuck, take 6 times 15)!
Hope this helped!!
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Answer:

Step-by-step explanation:
Because
is being multiplied by S, we can divide
from both sides of the equation. This will give us:
÷
But, that looks a bit hectic. Instead of dividing, you can multiply by the reciprocal (which is essentially how to divide fractions). So, instead of
÷
, you get:
×
When multiplying fractions, remember you can just multiply straight across-- numerator x numerator, then denominator x denominator.
By doing that, you get the fraction 
cannot be simplified any more, so S=
is your answer :)
I hope this helps