+(﹣7)=____,﹣(+1.4)=____,+(+2.5)=____,﹣+(﹣5)=____;﹣﹣(﹣2.8)=____,﹣(﹣6)=____,﹣﹣(+6)=____.
A的周长=____
B的周长=____
—I wonder if I park my car here.
—Of course it does. You need to find a safer place.