Please help me it would mean the world. A lot of points! The answer is 80cm^2 provided by my teacher I just need the work.

"you know, playing tennis is healthier than watching a tennis match on television," katya remarked to her couch potato brother. in this sentence, healthier is a/an a. superlative. b. comparative. c. positive form. d. adverb.

Aquantity with an initial value of 3900 decays exponentially at a rate of 35% every hour. what is the value of the quantity after 0.5 days, to the nearest hundredth?

For each proportion find the unknown number x 1/5/8=×/15