A local sandwich store has a fixed weekly cost of $520.00, and variable costs for making a roast beef sandwich are $0.60. Complete parts (a) through (c). a. Let x represent the number of roast beef sandwiches made and sold each week. Write the weekly cost function, C, for the local sandwich store. (Hint: The cost function is the sum of fixed and variable C(x) = (Use integers or decimals for any numbers in the expression.)