Please help i dont remember how to do this

What is the area of the triangle 10 13 12

Acompany manufactures three types of cabinets. it makes 110 cabinets each week. in the first week, the sum of the number of type-1 cabinets and twice the number of type-2 cabinets produced was 10 more than the number of type-3 cabinets produced. the next week, the number of type-1 cabinets produced was three times more than in the first week, no type-2 cabinets were produced, and the number of type-3 cabinets produced was the same as in the previous week.

When a valve is open 281 gallons of water go through it in one hour the number of gallons that would go through in 94 hours is