Want to generate several unique practice sheets and the key? This is the spreadsheet for you! Just hit F9 and the numbers change. The key is generated instantly. Use for a quiz or for an in class activity. I generate a set number of unique sheets and then have students group for peer assessment. On sheet 1 questions 1 and 2 are constant for examples. On sheet 2 all questions are varied.
See detailed description here: https://iteachphysics4all.wordpress.com/2015/05/31/measurment_metric/
Easily