You have to use 4 N of force to lift a 36 N object with a lever. The lever has an effort arm of 45 m. What is the load arm length?

The largest observatory complex in the world is on mauna kea, the tallest mountain on earth. what are some factors astronomers consider when selecting an observatory site? don’t forget practical ones. should astronomers, for example, consider building an observatory on denali (mount mckinley) or mount everest?