Answer the following with a complete solution

seatwork 1. The average age of publicjeepneys plying in Metro Manila is 18 years. Assume that the standard deviation is 4 years. If random sample of 81 publicjeepneys is chosen, find the probability that the mean ofjeepneys' age is: a. Between 15 to 21 years b. Over 18 years 2. It is reported that the average number of hours of sleep of college students during regular school days is 6 hours a day. If 27 college students were randomly selected, find the probability that the mean number of hours they sleep during regular school days is longer than 7.0 hours. Assume that the variable is normally distributed with a standard deviation of 1.3 hours