50. Apple Inc. sells four types of products: iPhones, MacBooks, iPads, and Apple Watches. The selling price and variable cost per unit for each product are as follows:

Product	Selling Price per Unit ($)	Variable Cost per Unit ($)
iPhone	$800	$500
MacBook	$1200	$800
iPad	$500	$300
Apple Watch	$300	$200

If the sales mix is 30% iPhones, 20% MacBooks, 40% iPads, and 10% Apple Watches, calculate the weighted average selling price and contribution margin per unit.