Can somebody help me please​

What is the smallest integer n such that n\sqrt{2} is greater than 20

You use math in day-to-day routines when grocery shopping, going to the bank or mall, and while cooking. how do you imagine you will use math in your healthcare career?

Which expressions equal 9 when x=4 and y=1/3 a. x2+6y b. 2x + 3y c. y2-21x d. 5 (x/2) -3y e. 3x-9y