Hello, please consider the following.
We know the following, right ?

So, here, it gives.

Do not hesitate if you need further explanation.
The initial number of trees is when t = 0:-
1500 * t^0 = 1500 so the answer is either a or c.
The value 1.02 represents a 2% increase so the answer is Option c.
51÷12= 4.25
just remember when your wondering how many times a number goes into something, divide the something by the number
He used 11 quarts out or 3 gallons .
I know because in 1 <span>gallon</span> there are 4 quarts .
You do 4*3 =12.
Than you -1 from 12 and get 11.
So,Your answer is He used 11 quarts out of 3 gallons.
Hope that helped.