Write the reaction involved in:
(a) Reimer-Tiemann reaction
(b) Kolbe's reaction
Phenol → aldehyde by Reimer; acid by Kolbe.
(a) Phenol + CHCl₃ + NaOH → ortho-hydroxybenzaldehyde
(b) Phenol + CO₂ + NaOH → salicylic acid

Study the diagram above and answer the following questions:
(a) How many alleles are involved in blood grouping?
(b) A person having 'AB' blood group has both dominant alleles. What is this inheritance type called?
(c) A man with 'A' blood group marries a woman with 'B' blood group. Can they have a child with 'O' blood group? Explain with the help of a cross.