That number in scientific notation is 1.26 * 10^-5. The decimal up front has to be greater than 1, but less than 10. We move the decimal to the left to get that answer 5 times. That is what gets us 1.26 * 10^-5.
Seven units long. The distance between 2 sides, in this example is 6, and -1. The distance between 6 and -1 is 7, so when you add units, you get 7 units.
