如图,在△ABC中,AB的垂直平分线交AC于点D, 交AB于点E,如果AC=5cm,BC=4cm,那么△DBC的周长是( )
A:6 cm
B:7 cm
C:8 cm
D:9 cm
This movie is very interesting. (改为感叹句)
____ ____this movie____
体积为1×10﹣3米3的小球浸没在水中,求小球受到的浮力F浮.