Selecting a Basis for Predicting Shipping Expenses (Requires Computer Spreadsheet) Cambridge SoundWorks sell portable speakers systems and bluetooth headphones. In an effort to improve the planning and control of shipping expenses, management is trying t determine which of three variables-units shipped, weight shipped, or sales value of units shipped-has the closest relationship with shipping expenses. The following information available: Weight Month Units Shipped Shipped (bs) Sales Value of Shipping Units Shipped Expenses May 10,000 7,500 $350,000 $38,000 June 12,000 1.760 432,000 42,000 July 15,000 9.200 420.000 50,100 August 20,000 10.500 400,000 72.500 September 12.000 7.600 October .000 6.000 300,000 41,000 x20,000 35.600 Required a. With the aid of a spreadsheet program, determine whether units shipped, weight shipped, or sales value of units shipped has the closest relationship with shipping expenses Complete the r-squared values between each possible independent variable and shipping expenses Round answers to two decimal places. Units shipped Weight shipped 0.94