当规模不经济存在时，总成本曲线开始（）
A.以递减的速度下降
B.以递减的速度上升
C.以递增的速度下降
D.以递增的速度上升
参考答案：A
What ______ public is concerned about is whether medical workers and scientists will be able to find_____cure for this new disease in a short time.
A．不填;不填
B．不填;the
C．the;不填
D．the;a
