199+299+399+…+29699,
=1+2+3+…29699,
=148×29799,
=444.
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随着龋病的发生,牙菌斑内哪些细菌数量下降
A.变形链球菌
B.血链球菌
C.乳杆菌
D.放线菌
E.酵母菌