1) find the value of the derivative (if it exists) of the function f(x)=x^2/x^2+81 at the extremum point (0,0) on the interval [-1,3]
a) 0
b) 1
c) -1
d) 1/10

2) a sector with central angle ѳ is cut from a circle of radius 13 inches, and the edges of the sector are brought together to form a cone. find the magnitude of ѳ such that the volume of the cone is a maximum.
a) √(4/3)π radians
b) (1/16)π radians
c) (2π√6)/3 radians
d) (1/8)π radians