A:∃x0∈R,x02+2x0+2>0
B:∃x0∈R,x02+2x0+2<0
C:∀x0∈R,x02+2x0+2≤0
D:∀x0∈R,x02+2x0+2>0
——Jack , you look tired today. What’s wrong?——I was ____busy_______ I didn't go to bed until midnight yesterday.
Ⅰ管:雌雄果蝇均为红眼
Ⅱ管:雌果蝇为红眼,雄果蝇为白眼
Ⅲ管:雌雄果蝇均是一半为红眼,一半为白眼
则Ⅰ、Ⅱ、Ⅲ三个试管中亲代红眼果蝇的性别分别是