3.1 RELATED RATES A 5 Test your Self The side of a cube increasing at a rate of 4 m/sec. Find the rate at which the volume of the cube increases when the side of the cube is 3 m. Aspherical balloon is being filled with air at the constant rate of 2 cm3/sec. How fast is the radius increasing when the radius is 3 cm ? The radius of a sphere is increasing at the rate of 3 feet/hour .At what rate is the spheres volume changing when the radius of the sphere is 10 feet? The radius of a circle increases at a rate of 2 cm sec. Find the rate at which the area of the circle increases when the radius is 3cm. The volume of a sphere decreases at a rate of 200 cm/sec. Find the rate at which the radius of the sphere increases, when the radius is 5 cm. C