Please find the area of this figure

i'm mainly confused on the height :/

Mr. murray wants to create 100 ounces of a mixture that is 62% pecans, 30% almonds, and 8% walnuts. how will the amount of mixture a compare to the amounts of mixtures b and c that mr. murray uses? he will use half as much of mixture a as he will use of mixtures b and c combined. he will use one-quarter as much of mixture a as he will use of mixtures b and c combined. he will use one-fifth as much of mixture a as he will use of mixtures b and c combined. he will use twice as much of mixture a as he will use of mixtures b and c combined.