Amarina rents boat slips monthly as listed below: $400, $350, $375, $325, $325, $350, $375, $275, $425, $320, $350, $475. they decide to raise their rates by $45. how will this affect the mean and the standard deviation? a) the mean and the standard deviation will remain the same. b) the mean will increase, and the standard deviation will increase. c) the mean will increase, and the standard deviation will decrease. d) the mean will increase, and the standard deviation will remain the same.