A computer​ company's cost​ function, which relates its average cost of production AC to its cumulative output in thousands of computers Q and its plant size in terms of thousands of computers produced per year q​ (within the production range of​ 10,000 to​ 50,000 computers), is given by ACequals 10minus0.10Qplus0.30 q. Is there a​ learning-curve effect? A​ learning-curve effect A. does not exist because average costs decrease as cumulative​ output, Q, increases. B. does not exist because average costs increase as current​ output, q, increases. C. exists because average costs decrease as current​ output, q, increases. D. exists because average costs increase as current​ output, q, increases. E. exists because average costs decrease as cumulative​ output, Q, increases.