It is easy to do, but requires some knowledge in JavaScript and HTML. Just add a JavaScript function that fetches the data and stores it into respective fields. If you look at the web page, you see that the form fields are named with the same names as the corresponding spreadsheet cells. You can make the new fields hidden and/or read-only.
No, but it is easy to write code in ASP, ASP.NET, JSP, PHP to insert and retrieve data.
If you have created a calculator, and there are some constants you want to set, for example the current rate, then read the following:
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