Base SI unit is the unit that used for simple quantity like time=second and length= meter. They only have one unit.
Derived unit is more complex because you multiply or divide at least two base SI, making it have more than 1 unit. The example could be velocity which was time/length = m/s
1 point energy should be the answer
I would say a. hope this helps
It's either 3 or 4 I know this becuase I have read a book about electricity
