Look at the image. Type the correct answer. Use numerals instead of words.

Which formula gives the area of a triangle? a=1/2(b+h)

Which one ? is the answer and how to find this answer

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?