Water pollution Oil is leaking out of a tanker damaged at sea. The damage to the tanker is worsening as evidenced by the increased leakage each hour, recorded in the following table.
$$\begin{array}{l|c|c|c|c|c|}
\text { Time (h) } & 0 & 1 & 2 & 3 & 4 \\
\hline \text { Leakage (L/h) } & 50 & 70 & 97 & 136 & 190
\end{array}$$
$$\begin{array}{l|c|c|c|c|}
\text { Time (h) } & 5 & 6 & 7 & 8 \\
\hline \text { Leakage (L/h) } & 265 & 369 & 516 & 720
\end{array}$$
a. Give an upper and a lower estimate of the total quantity of oil that has escaped after 5 hours.
b. Repeat part (a) for the quantity of oil that has escaped after 8 hours.
c. The tanker continues to leak $720 \mathrm{L} / \mathrm{h}$ after the first 8 hours. If the tanker originally contained 25,000 L of oil, approximately how many more hours will elapse in the worst case before all the oil has spilled? In the best case?