4. In a lot of microcircuits 0.2 are defective. 25 microcircuits are chosen at random to be tested. Find the probabilities that (a) less than 10 are defective. (b) in between 9 and 14 (exclusive) are defective. (5 points) 5. The burning time of an experimental rocket is a random variable having mean 4,76 seconds and variance 0.0016 second. What is the probability that this kind of rocket will burn (a) less than 4.66 seconds, (b) more than 4.80 seconds, (5 points)