Need help finding genotype and phenotype for #3 and #4

How much would it be worth in 5, 10, 20 years

The length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?

Your biology teacher chooses six students from a class of 26 to do a special project. determine how many total groups can be made. use either permutation or combination for the answer.