A student says that every time they add an element to a set, the number of subsets doubles. Is the student correct? Explain thoroughly

Write a recursive sequence that represents the sequence defined by the following explicit formula:

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Frank is lending $1,000 to sarah for two years. frank and sarah agree that frank should earn a real return of 4 percent per year. instructions: a. the cpi (times 100) is 100 at the time that frank makes the loan. it is expected to be 113 in one year and 127.7 in two years. what nominal rate of interest should frank charge sarah?