Refer to the following information to answer the questions below.
A man who is an achondroplastic dwarf with normal vision marries a colour-blind woman of normal height.The man's father was 6 feet tall,and both the woman's parents were of average height.Achondroplastic dwarfism is autosomal dominant,and red-green colour blindness is X-linked recessive.
-How many of their daughters might be expected to be colour-blind dwarfs?