Alice has 12 shells 1/6 of the shells are black. how many shells are black?

Can some one me with these questions

Your food costs are $5,500. your total food sales are $11,000. what percent of your food sales do the food costs represent?

The weight v of an object on venus varies directly with its weight e on earth. a person weighing 120 lb on earth would weigh 106 lb on venus. how much would a person weighing 150 lb on earth weigh on venus?