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 son of a colourblind father and normal homozygous mother marries to a daughter of normal father and heterozygous mother than their children will be

Which one of the following symbols and its representation, used in human pedigree analysis is correct?

Persons who are colour blind cannot distinguish

A normal woman whose father was colourblind marries a normal man. What kinds of children would be expected and in what proportion

Pick out the correct statements.

$I.$ Haemophilia is a sex-linked recessive disease

$II.$ Down's syndrome is due to aneuploidy

$III.$ Phenylketonuria is an autosomal dominant gene disorder

$IV.$ Phenylketonuria is an autosomal recessive gene disorder

$V.$ Sickle cell anaemia is an $X$-linked recessive gene disorder