798÷4≈( )
A:175
B:190
C:199
D:200
★★★★★
每行有____颗五角星,有____行,一共有____颗五角星。
— How are you? — I'm eight.
____应改为____
如图,平行四边形ABCD的对角线交于点O,且AB=5,△OCD的周长为23,则平行四边形ABCD的两条对角线的和是( )