Please help me. I don't understand the last question, so can you guys help me

What is the inverse of the function f(x)=2x+1

Which graph represents an even function?

An energy drink company claims that its product increases students' memory levels. to support its claims, the company issues advertisements claiming that 8 out of 10 people (chosen randomly from across the country) who tried their product reported improved memory. the missing component in this study is a .