In Mendel's dihybrid cross experiment,what is the number of offspring with the $RRYY$ genotype in the $F_2$ generation?

$A$ double heterozygous tall plant with yellow cotyledon colour is selfed. What is the ratio of dwarf plants with green cotyledon in the offspring?

The genotypes of a plant variety were $TtHh, Tthh, ttHh$ and $tthh$,where $T =$ tallness and $H =$ hairy stem. Which one of the following crosses would produce progeny giving a phenotypic ratio approximately $1 : 1 : 1 : 1$?

If the gametes of an individual are $RY$ and $Ry$ only,then the genotype of the same individual will be . . . . . . .

In a dihybrid cross,$80$ plants are obtained. The ratio of homozygous and heterozygous plants shall be:

In a typical Mendelian dihybrid cross,one parent is homozygous for both dominant traits and another parent is homozygous for both recessive traits. In the $F_2$ generation,both parental combinations and recombinations appear. The phenotypic ratio of parental combinations to recombinations is