In many cases, developer has to maintain and develop code written by someone else. Look at the HTML code and JavaScript code below. Study how does it work and what is the logic behind it.
Then add following features to the code:
a) the values read from the text boxes are stored as strings. Modify the code to store the quantity as an integer and the price, tax and discount as floats.
b) modify the JS code to double the discount applied when the quantity ordered is greater than 100 items
c) modify the HTML form to include a shipping field, and include this value in the total calculation in shopping.js.