How to solve this question? i have to have 3 solutions

Atriangle with all sides of equal length is a/an triangle. a. right b. scalene c. equilateral d. isosceles

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!

Linda loans her friend $250 with a 5% monthly intrest rate. how much was the whole loan?