33.At t = 0 the switch S is closed with the capacitor uncharged. If C = 30 µF, ε = 30 V, and R = 5.0 kΩ, at what rate is energy being stored in the capacitor when I = 2.0 mA? 
(A) 15 mW
(B) 40 mW
(C) 45 mW
(D) 70 mW
(E) 90 mW
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統計: A(1), B(2), C(0), D(1), E(0) #3427033
統計: A(1), B(2), C(0), D(1), E(0) #3427033