How many pairs of chromosomes are involved in Mendelian dihybrid crosses and dihybrid crosses with linkage,respectively?

In a dihybrid cross between a pure tall pea plant with green pods and a dwarf pea plant with yellow pods,how many dwarf plants with yellow pods will be produced in the $F_2$ generation out of $16$ offspring?

In humans, brown eyes $(B)$ are dominant over blue $(b)$ and dark hair $(D)$ are dominant over red hair $(d)$. A man with brown eyes and red hair marries a woman with blue eyes and dark hair. They have two children; one resembles the man (brown eyes, red hair), and the other resembles the woman (blue eyes, dark hair). What are the genotypes of the man and the woman?

In the $F_2$ generation of a dihybrid cross of homozygous parents,the number of genotypes and phenotypes will be respectively . . . . . . .

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

In Mendel's experiments with garden pea,round seed shape $(RR)$ was dominant over wrinkled seeds $(rr),$ and yellow cotyledon $(YY)$ was dominant over green cotyledon $(yy).$ What are the expected phenotypes in the $F_{2}$-generation of the cross $RRYY \times rryy$?