15 POINTS! PLEASE HELP! WILL GIVE BRAINLIEST! Which expression should you simplify to find the 90% confidence interval for a sample of 36 people with a mean of 64 and standard deviation of 4? O +2 A. 36 2. VOA O B. 64 +2 4 V36 O C. 64 +1.645. 4. V36 4 O D. 36 +1.645 V64 SUBMIT​

He ! a group of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?