A:y-3x=62y+x=-4
B:y-3x=62y-x=4
C:3x-y=63x-y=4
D:3x-y=-62x-y=4
某水库中人工养殖了青鱼、草鱼、鲢鱼、鳙鱼、鲫鱼、鲤鱼,为了提高鱼类的产量,必须不断投放饵料。请回答下列问题:
A large park ________here now.They hope to finish it in three months.