The charge to ship a package from one town to another, C, is given below as a function of the weight of the object, w, in pounds.

C = $3.50 + $0.55w

If the shipping cost for Cathy's item was $7.02, what was its weight?
A. 6.4 pounds
B. 64 pounds
C. 16.4 pounds
D. 0.64 of a pound