Carson Wood Products processes logs into four grades of lumber totaling 500,000 board feet as follows at a joint cost of $300,000:

Grade	Board Feet	Final Sales Value
First and second	75,000	$ 56,250
No. 1 common	200,000	180,000
No. 2 common	100,000	105,000
No. 3 common	125,000	127,500

What amount of joint costs will be allocated to No. 2 common using the constant gross margin percentage method?

a.$192,000

b.$67,200

c.$37,800

d.$300,000