What is the answer to this problem here? 30 points to whoever tells me!

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

Which situation can be modeled by the inequality 5 + 10w ≥ 45? a. you start with $5 and save $10 a week until you have at least $45. b. you start with 5 baseball cards and purchase 10 cards every week until you have at most 45 cards. c. you start with 5 water bottles and purchases cases of 10 water bottles each until you have a total of 45 water bottles. d. you spend $5 plus $10 per week until you have less than $45.

What is x3+3x2−16x−48 divided by x−1?