影响钙磷代谢的物质是
A.砷B.氟C.钙D.磷E.硫氰酸盐
参考答案:B
Thanks taking care of my cat. [ ]
A. to
B. in
C. for
D. of
粗产物乙酸正丁酯依次经水洗、碱洗、水洗,其目的是什么?