Evaluate 13-0.75w + 8x when w equals 12 and x equals 1/2

Can someone me with the property questions for 12 13 and 14 plz

Which of the following graphs could represent a cubic function?

Astudent draws two parabolas both parabolas cross the x axis at (-4,0) and (6,0) the y intercept of the first parabolas is (0,-12). the y intercept of the second parabola is (0,-24) what is the positive difference between the a values for the two functions that describe the parabolas