In Mendel's monohybrid cross,$T$ and $t$ are ......... of each other.

In humans,how many genotypes and phenotypes are produced by the three different alleles of the $ABO$ blood group system?

$ABO$ blood groups in humans are controlled by the gene $I$. It has three alleles: $I^A, I^B$ and $i$. Since there are three different alleles, six different genotypes are possible. How many phenotypes can occur?

In humans,multiple alleles are seen controlling the inheritance of which of the following?

The genotypes of a husband and wife are $I^AI^B$ and $I^Ai$ respectively. How many different genotypes and phenotypes are possible among their children?

In $ABO$ blood grouping,there are $P$ genotypes and $Q$ phenotypes.
$\quad P \quad\quad Q$