Help me- 3.4 + 12a / 4 for a = 10

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.

Fixed rate mortgage offer: purchase price: $170,000 down payment ($34k): 20% term: 30 years interest rate: 4.25% property tax (yearly): $1,500 homeowner’s insurance (yearly): $1,000 use this example from a fixed-rate mortgage calculator to you answer the questions. keep the page open after you complete this question. according to the calculator, the monthly payment demarco and tanya should anticipate paying for principal and interest is $208. $877. $669. $1,200.

Study results indicate that the mean length of time people spend on a bus in a city is between 21.2 min and 24.5 min what is the study margin of the error?