【简答题】如图,AB是⊙O的直径,弦CD⊥AB,垂足为E,如果AB=10,CD=8,那么sin∠OCE= .
【简答题】如图,AB是⊙O的直径,弦CD⊥AB,垂足为E,如果AB=26,CD=24,那么sin∠OCE=
【单选题】Hundreds of species of marine life manage to survive even in the darkest depths of the ocean. These tenants of the deep have evolved some extremely ingenious devices for locating their food and enemie...
A.
learned to live without light
B.
evolved ingenious devices to help them
C.
found ways to supply their own light
D.
developed extremely sensitive eyes
【单选题】一梁拟用图示两种方式搁置,则两种情况下的最大应力之比 为:
【单选题】一梁拟用图示a.b两种方式搁置,则两种情况下的最大应力之比【图片】
【单选题】一梁拟用图示两种方式搁置,则两种情况下的最大应力之比为( )。【图片】