Problem $2.$ Water flows from the bottom of a storage tank at rate of r$($t$)=200-4$t liters per minute,

where t Find the amount of water that flows from the tank during the first $10$ minutes.

Problem $3.$ When records were first kept $($t$=0),$ the population of a rural town was $250$ people. During

the following years, the population grew at a rate of P$^(\text{'})($t$)=30(1+\backslash$sqrt$($t$)),$ where t is measured in years.

$($a$)$ Find the population after $9$ years.

$($b$)$ Find the population P$($t$)$ at any time t$>=0$