根据相反数的定义,可知:-(-512)=512.
故答案为:512.
A lot of animals are in danger now because people forests. [ ]
A. fall down
B. come down
C. cut down
D. break down
人体最主要的造血部位在:()
A、肝脏
B、骨髓
C、脾
D、血管内