QUESTION 15 dle accident left him disabled. After long months of therapy, he hired an experienced luthier and started a small shop to make and sell Spanish guitars. The guitars sell far $900, and the fixed monthly operating costs are as follows: ent and utilitie Martin's accountant told him about contribution margin ratios, and o s5 wento coverins abed costs and adMlartin understood clearly that for every dolar of Martin wishes to earn $4000 of operating profit each month. Calculate the number of guitars Martin will need to sell to achieve the target profit. (Round your answer up to the nearest whole guitar.) 4 guitars 12 guitars O 3 guitars O13 guitars