一个圆锥与一个圆柱等底等高,圆锥的体积是圆柱体积的______.
因为等底等高的圆锥的体积是圆柱的体积的13,
故答案为:13.
Welcome our home. a seat , please. [ ]
A. in , Get
B. to , Have
C. at , Give
D. for, Take
供人类呼吸的气体是( )
A.氧气
B.氮气
C.二氧化碳
D.稀有气体