What is haemophilia?

What is the pattern of inheritance in haemophilia? Give reason.

Haemophilia is

If a boy's father has haemophilia and his mother has one gene for haemophilia, what is the chance that the boy will inherit the disease

A phentypically normal couple has two normal daughters and a son affected with haemophilia.What is the probability that both the daughter are heterozygous carries ?

If a boy's father has haemophilia and mither is heterozygous what is the chance that the boy will inherit haemophilia

If a boy's father has haemophilia and mother is heterozygous what is the chance that the boy will inherit haemophilia