16.find the sum of 56+(-12)
a.43
b.44
c.-43
d.-44
17.find the sum of 12+3
a.24
b.25
c.-24
d.-25
18.find the difference of 12-(-12)
a.24
b.-24
c.0
d.-12
19 find the difference of -7-5
a.12
b.2
c.-12
d.-2
20.find the product of (-5)(-6)
a.11
b.-11
c.30
d.-30​