I really need help please​

What is the area of a pizza with a radius of 40 cm leave the answer in terms of π to find your exact answer 40π cm² 1600π cm² 800π cm² 80π cm² π=pi

Can someone me do math because i am having a breakdown rn because i don’t get it

At oaknoll school, 90 out of 270 students on computers. what percent of students at oak knoll school do not own computers? round the nearest tenth of a percent.