An oil pipeline sprang a leak, but was repaired in 20 minutes. At certain times, super top-secret government sensors installed in the pipeline measured the rate at which the oil was lost. The information is given in the following table:

Minutes after break 1 3 4 6 6.5 8 10 11.5 13 15 16 19

Oil loss rate (gallons/minute) 5.1 4.3 4.0 4.1 4.2 5.7 6.4 7.0 7.5 7.7 4.5 2.1

(a) Give an estimate of the total amount of oil lost during the 20 minutes. How would you do this?

(b) Give another estimate of the total amount of oil lost (different than in part (a)).

(c) Suppose L(t) was the function giving the rate of oil loss at time t minutes after the break. Based just on this, state the exact total amount of oil lost during the 20 minutes.