Calculate the final concentration of salicylic acid when mixing Whitfield's Ointment (contains 3% salicylic acid), 30g, with Lassar's Paste (contains 2% salicylic acid), 60g, and White soft paraffin to a total of 200g. A) 1.5% B) 2% C) 2.5% D) 3% E) 3.5%