长江中下游平原和四川盆地相同的主要农作物为( )
A:稻谷、棉花、淡水鱼
B:柑橘、棉花、稻谷
C:桑蚕、甘蔗、柑橘
D:稻谷、油菜籽、桑蚕
____ with a new type of machine, the explorers went into a cave, hoping to find some buried treasure.
15÷( 512 + 56 )=____