Answer:
The cross between plants with genotype Yyrr and yyRr and gametes that are proces by them are:
gametes that the Yyrr individual can produce - Yr or yr.
The YyRr individual can produce - YR, Yr, yR, or yr.
The possible genotypes are shown in the punnet square.
For a pea to be yellow and wrinkled, it would have the genotype YYrr, or Yyrr (as yellow is dominant (Y) and wrinkled is recessive (r)).
Therefore, we count the number of those genotypes of the total genotypes we get are shown in punnet square..