Since he possess an X - linked disorder, thus in case if it is crossed with a mother with XX genotype
Thus, X'Y * XX
X'X, X'X, XY, XY
Thus, it is clear that a male child will carry Y chromosomes from his father and X chromosome from her mother. Thus, in order to have X-linked disorder, the male child must receive an affected X allele from his mother.
Hence, the probability of son inheriting an X-linked disorder from his father would be zero.
X-linked disorder is a recessive autosomal disorder, which means that
There is a 1 in 4 chance (25%) of having a child who is unaffected.
There is a 1 in 4 chance (25%) of having a child who is affected by the condition. These children have two copies of the gene that do not work correctly.
There is a 1 in 2 chance (50%) of having a child who is a carrier of the condition. These children have one working copy of the gene and one copy of the gene that does not work correctly.
The Doppler Effect is hard for me to put into words, but a common example is that when you stand still on the side of the road, you notice how the pitch of a fire engine's siren changes from when it's coming towards you vs driving away.