A:催化剂
B:过氧化氢分解的速率
C:产生气泡量
D:试管中的过氧化氢溶液的量
74+19=____
—I'm not sure I can go to your party next week.
—Well. you come,I'll be very glad.
△ABC中,∠A:∠B:∠C=1:2:3,最小边BC=5cm,最长边AB的长是( )