Find the annual interest rate. I - $893.75, P = $5,500, t = 30 months

At noon a tank contained 10cm water. after several hours it contained 7cm of water. what is the percent decrease of water in the tank?

Lines a and b are perpendicular. if the slope of line a is 3, what is the slope of line b?

Nour and rana are shopping for a christmas tree. they are deciding between 2 22 different types of trees (real and fake) and 4 44 colors for the ornaments (white, silver, gold, and purple). they each created a display to represent the sample space of randomly picking a type of tree and a color for the ornaments. whose display correctly represents the sample space?