Choose the correct answer and Fill in the blanks:
0+-5=__.-5/+5
Consider
0+-50-5=-5
Hence, 0+-5=-5
-1--1=__.0/-2
-1+___=+5.-6/+6
-72--90=_____.+18/-162
-4+(___)=-12.-8/+8
35--20=_____.55/15