This is in Differential Calculus. This is only multiple choice. Provide necessary solutions for each items. Follow the numbering thank you and Godbless.

= 4.00. dy 1. Given = =X = 6.00 when x = 7.00 and y = 12.00. Find A) 7.20 C) 8.23 B) 9.15 D) 12.43 2. How fast is the surface area of a sphere increasing when its radius is 10 em and increasing at the rate of 3 cm/sec? The surface area of a sphere is S = 4xr. A) 676 cm /sec C) 754 cm /sec B) 877 cm-/sec D) 456 cm-/sec 3. How fast is the volume of a cube increasing at the instant that its edge is 10 em long and all edges are each increasing at the rate of 3 cm/sec? A) 690 cm /sec C) 1200 cm /sec B) 450 cm /sec D) 900 cm /sec