Does this graph show a function? Explain how you know​

What is the solution to the equation? k/6.4=8.7 2.3 5.568 15.1 55.68

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.  

Calculate the total payback for a $3,500 loan at 8% annual interest with monthly payments for two years. show all of your steps. use the formula, m = pm(1 + m)^na/(1 + m)^na - 1, as needed.