In 2014, a research company found that the average person sent 30 text messages per day, the population standard deviation being 7.5, and this data is normally distributed. One research analyst suspects this number to be low and wishes to determine if this number is still accurate. A random sample of 25 people found the average was 35.5 per day with a standard deviation of 8. Can the analyst conclude that the number of texts sent per day is higher than 30?" a. What kind of hypothesis test is this? b. Explain why you chose your answer from part a