1.For a medical study, a researcher wishes to select people in the middle 74% of the population based on blood pressure. If the mean systolic blood pressure is 120 and the standard deviation is 8, find the upper and lower readings that would qualify people to participate in the study.

2. the time to finish exam is approximtely normal with a mean of 50 and standard deviation of 8 minutes. how much time should be given to complete the exam so that 80% of the students will complete the exam in given amount of time?

please show step by step work i have 1 hour..