PLEASE HELP ILL MAKE BRAINLIEST Which of the following is a monomial?

A.) 3/x

B.) 5x^2 + 2x + 3

C.) 4x

D.) sqre x-1

Which of the following expressions is equal to 2x^2+8

Which line is parallel to the line that passes through the points (2, –5) and (–4, 1) a. y=-x+5 b. y=-2/3x+3 c. y=2/3x-2 d. y=x+5

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of