If a normal man had a grandfather with hemophilia and has a wife who is not a carrier is there any possibility of having children that are homophiliac?

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?

The energy required to vaporize a certain amount of a substance is greater than the amount of energy necessary to raise the temperature of the same amout of that substance by 1 degreee celcius

Which of these is a provisioning service people get from the ocean