白鲟产于我国钱塘江、长江,以鱼、虾为食;匙吻鲟产于(),以浮游生物为食。
参考答案:北美
Everyone showed great enthusiasm for the Drama Festival _____ age, class or English level. [ ]
A. according to
B. due to
C. regardless of
D. in the presence of
下列分散系中,分散质微粒直径最大的是
A.糖水
B.石灰乳
C.氢氧化铁胶体
D.淀粉溶液