完成下列单位换算:
72km /h =__________m/s,7.2 g/cm3 =________kg/m3
20;7200
—______ behind ______?
—My alarm clock. [ ]
A. What's; the chair
B. Where's; the chair
C. What are; the chair
D. Where are; a chair
()又称遗传学第一定律。
A、分离规律
B、自由组合定律
C、连锁遗传定律