Blake’s Blacksmith Co. produces two types of shotguns, a 12-gauge and 20-gauge. The shotguns are made through a joint production process that ultimately produces 30 12-gauge shotguns and 20 20-gauge shotguns and costs a total of $4,000 per batch. After the split-off point, each type of shotgun goes through an additional crafting process before it is sold. The additional production process of the 12-gauge shotgun costs $30 per gun, after which it is sold for $180 per gun. The additional production process of the 20-gauge shotgun costs $25 per gun, after which it is sold for $150 per gun. Determine the amount of joint production costs allocated to each type of shotgun using the physical units method.