Raven purchases a new cell phone for $700 that depreciates annually. The value of her cell phone per year, x, can be modeled by the exponential function f(x)=700(0.86)^x. What is the range of this exponential function in terms of the context of the problem?
a. (0,700]
b. [0,∈fty )
c. (700,∈fty )
d. R
