微分方程y″+3y′=sinx的阶数是______.
参考答案:C
___________ was no doubt __________ someone had broken into the store the day before.
A.There; that
B.There; whether
C.It; that
D.It; whether
药物配伍具有"分经论治"特点的方剂是()
A.败毒散
B.大青龙汤
C.九味羌活汤
D.独活寄生汤
E.羌活胜湿汤