A woman who has haemophilia marries a normal man. How many of their children will have haemophilia and what is their sex?

Explanation

To solve the problem of how many children of a woman with hemophilia and a normal man will have hemophilia and what their sex will be, we can follow these steps:

### Step 1: Understand the Genetics of Hemophilia
Hemophilia is a sex-linked recessive disorder, which means that the gene responsible for hemophilia is located on the X chromosome. Females have two X chromosomes (XX), while males have one X and one Y chromosome (XY).

### Step 2: Determine the Genotypes
- The woman with hemophilia has the genotype XhXh (where Xh represents the X chromosome with the hemophilia allele).
- The normal man has the genotype XY (the X chromosome is normal).
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