I need help with 25. 26. And 27 plz I don’t know how

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?

Dakota earned $7.50 in interest in account a and $18.75 in interest in account b after 15 months. if the simple interest rate is 4% for account a and 5% for account b, which account has the greater principal? explain. to make it a little easier, there is an image. good luck!

Acircus act has 3 times as many elephants as acrobats. jorge noticed that all together there were 56 legs in the circus ring. how many elephants were in the show?