Is the sum of two polynomials a constant polynomial or a variable?

Find the sum of 4x^{2} -4+6 and -7^{2} +3x+1

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

Find the value of ax 4 ; a = 2, x = 1. select one: a. 2 b. 4 c. 1 d. 8