A:remained to be done
B:remaining to be done
C:remained being done
D:remaining to do
用计算器求下列各式的值:
(1)sin47°;
(2)sin12°30′;
(3)cos25°18′;
(4)tan44°59′59″;
(5)sin18°+cos55°﹣tan59°.
鸟卵的结构中能为胚胎发育提供养料和水分的是( )