Here's the question you clicked on:
GalaxyS
if oil leaks from a tank at a rate of r(t) litres per minutes at time t, what does what does integral r(t) dt from 0 to 120 represent?
total leakage at the end of 2 hours
yes... that's right. the integral would represent the total volume (in liters) that has leaked in the two hour period.
@GalaxyS integration basically sums up the function from lower limit to upper limit, and since limits are from 0 to 120 and r(t) is leage per minute so integration from 0 to 120 will sum up the lekage for 120 minutes thats 2 hours