In the $F_2$ generation of a Mendelian monohybrid cross,how many individuals retain the parental genotypes (in $\%$)?

In Mendel's monohybrid cross experiment,the phenotypic ratio is $P$ and the genotypic ratio is $Q$. Select the correct option for $P$ and $Q$.
$\quad \quad \quad P \quad \quad \quad Q$

Describe one gene inheritance.

$A$ heterozygous tall plant is crossed with a dwarf plant. The proportion of dwarf plants in the offspring will be: (in $\%$)

If two individuals with genotype $Bb$ are crossed and they produce two offspring,what is the probability that the second offspring will show the recessive trait,given that the first offspring shows the dominant trait?

In a cross between $AaBB$ and $aaBB$,what will be the ratio of the genotypes $AaBB$ and $aaBB$ in the progeny?