Correct Answer - C
Let `deltal`= total enlogation of the bar, A = area,
`E= 8 xx 10^(2)`. Let make the free body diagram .
Using equation `deltal= (1)/(AE)(F_(1)l_(1) + F_(2)l_(2) + F_(3)l_(3))`
`deltal =(1)/(10 xx 8 xx 10 ^(2))(5 xx 60 + 2 xx 60 + 1 xx120)`
`deltal=0.0675 cm`