Jenny is x years old ,thomas is 3 times older. jenny is older than ali by 5 years if x =12. how much older is thomas?

Is a positive integer raised to a negative power always positive

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.

98 point question what is the record for most points in one