Please help me with these 2 questions

The weight of a pomelo is normally distributed. A consumer is interested in the average weight of pomelos. In a random sample of twelve pomelos, the average weight is determined to be 1301 g with a standard deviation of 168 g. Construct a 99% confidence interval for the population mean weight. O a. (1257.5160, 1344.4840) O b. (1150.3670, 1451.6330) O C. (1152.8404, 1449.1596) O d. (1176.0706, 1425.9294) A 95% confidence interval for p1 - p2 is calculated to be (0.1823, 0.3001). If the level of confidence is now decreased to 90%, what happens to the confidence interval? O a. Unknown O b. It increases in size O c. It decreases in size O d. It remains the same