A composite bar made of Aluminium and Steel is fixed rigidly at supports P and Q as shown in figure. When the temperature of the bar is increased by $$10^\circ C$$, the reactions at the supports are (given $$E_{al} = 70 GPa, E_s = 210 GPa, \alpha_{al} = 11E - 6$$ mm/mm$$^\circ C$$ and $$\alpha_s = 12E - 6 mm/mm^\circ C$$)

A

4060 N

B

6780 N

C

12240 N

D

2412 N