Which law did Mendel propose based on the inheritance of two traits?

In peas,tallness is dominant over dwarfness and red colour of flowers is dominant over the white colour. When a tall plant bearing red flowers was pollinated with a dwarf plant bearing white flowers,the different phenotypic groups were obtained in the progeny in numbers mentioned against them:
Tall,Red $= 138$
Tall,White $= 132$
Dwarf,Red $= 136$
Dwarf,White $= 128$
Mention the genotypes of the two parents and of the four offspring types.

In Mendel's dihybrid cross,what is the probability of obtaining a homozygous recessive plant in the $F_2$ generation?

From a mating of two dihybrid individuals $(AaBb \times AaBb)$,how many of the $16$ possible zygote combinations would be expected to be homozygous dominant for both genes?

In the $F_2$ generation of a dihybrid cross,how many plants possess the same genotype as the parental generation?

In a dihybrid cross,when $F_1$ plants $(RrYy)$ are self-hybridized,what is the segregation ratio of yellow and green seeds in the $F_2$ generation?