$\"\"$

Oil storage tank starts leakage at time $\"\"$ .

Rate at which the oil leaks from the tank is $\"\"$ liters/min.

Find the amount of the oil that leaks from the tank during the first hour.

Limits of the integral are $\"\"$ and $\"\"$ min.

Consider the amount of the oil that leaks from the tank during the first hour as $\"\"$ .

$\"\"$ .

Consider $\"\"$ .

Differentiate on each side with respect to $\"\"$ .

$\"\"$

Change of integral limits:

If $\"\"$ , then $\"\"$ .

Substitute $\"\"$ , $\"\"$ and change of limits in the integral.

$\"\"$

Amount of the oil that leaks from the tank during the first hour is $\"\"$ lt.

$\"\"$

Amount of the oil that leaks from the tank during the first hour is $\"\"$ lt.