Let S be a set of n numbers. Let X be the set of all subsets of S of size k, and let Y be the set of all ordered k-tuples (s1, s2, , sk) such that s1 < s2 < < sk. That is, X = {{s1, s2, , sk} | si is in S and all si's are distinct}, and Y = {(s1, s2, , sk) | si is in S and s1 < s2 < < sk}. (a) Define a one-to-one correspondence f : X → Y. Explain why f is one-to-one and onto. (b) Determine |X| and |Y|.

|X| =

|Y| =

Can someone please answer part b of this question. The answer available is incorrect and unclear.

Leonardo wrote an equation that has an infinite number of solutions. one of the terms in leonardo’s equation is missing, as shown below.

On the blueprint of a house, 42 millimeters represents 8 meters. the actual lehenth of the living room is 5 meters. what is the length on the blueprint

Woodland bicycles makes two models of off-road bicycles: the explorer, which sells for $250, and the grande expedition, which sells for $350. both models use the same frame, but the painting and assembly time required for the explorer is 2 hours, while the time is 3 hours for the grande expedition. there are 375 frames and 450 hours of labor available for production. how many of each model should be produced to maximize revenue? a. 200 explorers 50 grande expeditions c. 225 explorers 0 grande expeditions b. 150 explorers 10 grande expeditions d. 325 explorers 50 grande expeditions