Question: Raindrops are falling at an average rate of 30 drops per square inch per minute.
a) What is the chance that a par5ticular square inch is not hit by any drops during a given 10-second period?
b) If each drop is a big drop with probability 2/3 and a small drop with probability 1/3, independently of the other drops, what is the chance that during 10 Seconds a particular square inch gets hit by precisely four big drops and five small ones?