3T 3i 1 Homework 5 List, page 3 of4 Problem 4) In 2012, the percent of American adults who owned cell phones and used their cell phone to send or receive text messages was at an all-time high of 80%. Assume that 80% refers to the population parameter rt. More recently in 2016, a polling firm contacts a simple random sample of 110 people chosen from the population of cell phone owners. The firm asks each person "do you use your cell phone to send or receive texts? Yes or no." a) The rm calculates the sample proportion of people who answer yes they send/receive texts. This is [3. Before the firm analyzes the data, they want to show that p is approximately normally distributed. Show that the normal approximation for p is valid by verifying the three conditions. Show the arithmetic. b} What is the approximate distribution of f5: give the shape, mean, and standard deviation. When you calculate the standard deviation, round to 2 nonzero decimals. For example, ifyou calculate a"; to be 0.01234, round to 0.012. (To round, remember if it's 4 or below, let it go. If it's 5 or above, give it a shove.) c) What is the probability that p is between 78% and 82%: what is P(0.78