How do you make 30 with only 1, 4, 5 and -5?

If a baby uses 15 diapers in 2 days how many diapers will the baby use in a year

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 .

What is x and y intercepts for y=x+7