JavaScript：如何将单选按钮和复选框的总和放入输入框（初学者）

I am trying to get the sum of radio button and checkbox on the click of the calculate button. The usps button is supposed to be and the ups button is supposed to be 2.50. I cannot figure out how to just add that amount to the calculated value. I can only get the sum of the quantity*price and the gift wrap option. Thank you for all you help! Here is my code. I am guessing most of the work has to be done within the function calculatetotal()I am trying to get the sum of radio button and