1/2+(1/2)2+(1/2)3+(1/2)4的值等于()
A.1/16
B.7/8
C.15/16
D.1
参考答案:C
Fortunately, the illness is fully treatable if _____ within ten days. [ ]
A. being found
B. find
C. finding
D. found
普通小麦成熟花粉粒含有三个染色体组,用这种花粉培养成的植株是()
A.单倍体
B.二倍体
C.三倍体
D.多倍体