Find the missing number to complete the linear equation that gives the rule for this table This is 7th grade accelerated math
Pls help ASAP this is due soon

Arandom sample of 45 observations results in a sample mean of 68. the population standard deviation is known to be 23 a. compute the margin of error at a 959% confidence interval. b. compute the 95% confidence interval for the population mean c. compute the 90% confidence interval for the population mean. d. compute the 75% confidence interval for the population mean