Help me on number 4 you get brainliest

If x + 10 = 70, what is x? a. 40 b. 50 c. 60 d. 70 e. 80

Is this a polynomial function? i need to know asap

Acylinder with a base diameter of x units has a volume of jxcubic units which statements about the cylinder are true? check all that apply. the radius of the cylinder is 2 x units. the radius of the cylinder is 2x units. the area of the cylinder's base is 200 square units. the area of the cylinder's base is a square units. the height of the cylinder is 2x units. the height of the cylinder is 4x units. mark this and return save and exit next submit