Question

Why do you think the U.S. hasn't fully adopted the metric system?

Answer 1

France tried to send a kilogram, but some pirates stole it and the us had to use us. customary

Answer 2

From what I know, when everyone else was switching to the metric system, the US could not because it was TOO EXPENSIVE!

This would have meant changing the numbers on all road signs from miles to kilometers. All the spedometers on cars would also need to be changed. It was a better option to just remain with the imperial system for the sake of the cost.