Answer:
Four satellites are needed to find your location. GPS's get the signal from satellites and that can calculate the distance you are from those satellites and location. the satellites emit high frequency low power signals that your GPS can pick up.
Explanation:
Answer:
Fine focus.
Explanation:
If you're referencing a microscope, then it would be fine focus. Coarse focus is a basic focus used to properly see a specimen, while fine focus enhance clarity and precision. To use both, you have to gently twist a knob until you can see the specimen at a desired clarity.
Here's a reference image if you need it, it's labeled all the parts of a microscope.