2 1/4 + 8/3 what is the answer

An an average person has 6×10 by the power of two as many red blood cells as white blood cells a small sample of the blood has 7×10 by the power of three white blood cells about how many red blood cells are in the sample

Pls if a cow has a mass of 9×10^2 kilograms, and a blue whale has a mass of 1.8×10^5 kilograms, which of these statements is true?

What are the solutions of the system? solve by graphing. y = -x^2 - 3x + 2 y = -2x + 2