A:血浆、血清
B:血浆、血浆
C:血清、血浆
D:血浆、组织液
如图,⊙O的半径为2,AB、CD是互相垂直的两条直径,点P是⊙O上任意一点(P与A、B、C、D不重合),经过P作PM⊥AB于点M,PN⊥CD于点N,点Q是MN的中点,当点P沿着圆周转过45°时,点Q走过的路径长为( )
已知等比数列{an}满足an+1+an=4×3n﹣1(n∈N*).
(I)求数列{an}的通项公式;
(Ⅱ)若bn=log3an,求Tn=b1b2﹣b2b3+b3b4﹣b4b5+…+b2n﹣1b2n﹣b2nb2n+1.
图中a表示基因工程,c表示胚胎工程d表示细胞工程,则e和b分别表示
A. Because l can go swimming. B. These books are Tom's C. Yes, it is.
D. She is shopping E It's near the school.