The radius of the sphere decreases at the rate of 6 m/ sec
That is, 
Surface Area of the sphere of radius r is given by 
Differentiating with respect to t,


The answer is 5+b, so when b= 14.99, then 5+14.99=$19.99
hope this helps!
Shoot two arrows worth 16 points each (32 points)
Given:
Square pyramid with lateral faces.
646 ft wide at the base.
350 ft high.
Because of the term lateral faces, we need to get the lateral area of the square pyramid.
Lateral Area = a √a² + 4 h² ; a = 646 ft ; h = 350 ft
L.A. = 646 ft √(646ft)² + 4 (350ft)²
L.A. = 646 ft √417,316 ft² + 4 (122,500 ft²)
L.A. = 646 ft √417,316 ft² + 490,000 ft²
L.A. = 646 ft √907,316 ft²
L.A. = 646 ft * 952.53 ft
L.A. = 615,334.38 ft²