Write a function **compositions** that takes two natural numbers $k$ and $n$ as inputs and returns the set of all tuples of size $k$ that sum to $n$.

Which best describes the role or restriction enzymes in the analysis of edna a. to break dna into fragments that vary in size so they can be sorted and analyzed b. to amplify small amounts of dna and generate large amounts of dna for analysis c. to purify samples of dna obtained from the environment so they can be analyzed d. to sort different sizes of dna fragments into a banding pattern that can be analyzed

Effective character encoding requires standardized code. compatible browsers. common languages. identical operating systems.

Which player type acts on other players? a. killer b. achiever c. explorer d. socializer