Answer:

Step-by-step explanation:
The radius, r of the expanding circle of oil is modeled by the function:
, where s is time in seconds.
When s=5
Radius 
Area of a circle 
Therefore, the area of the oil spill when s=5 seconds

The area of the spill when s=5 seconds is 45pi square inches.
Answer:
$450
Step-by-step explanation:
Let E be the amount of money Ethan starts with, J be the amount Jun Wei starts with, and R be the amount Raj starts with. Let M be the total amount of money to start with.
To start:

This means Ethan has 5/20 of M, the money to start with. This reduces to 1/4 of M.
Afterwards:

This means Ethan has 3/13 of the remaining money (which is M-50!) after giving up 50. So
E = (M/4), or 4E = M
and

We know 4E = M, so we can substitute that in:

That's how much money Ethan had to start with. But we're asked how much he has AFTER giving $50 away, so that's $450.
Five tens are in 54, with 4 ones left over. hope this helped!!
Hello There!
<u><em>The volume of a cylinder is pi * r^2 * h. It's a circle times the height. </em></u>
<u><em></em></u>
<u><em>The volume of a cone is (1/3) * pi * r^2 * h. So it is one third of the volume of a cylinder with the same dimensions. </em></u>
Two equivalent fractions to 3/4 are 6/8 and 12/16!