Answer:
Although you normally hear about trying to reduce or eliminate friction, it actually has some important uses.
Since friction is a resistance force that slows down or prevents motion, it is necessary in many applications where you might want to hold items or do things and prevent slipping or sliding. In those cases, there is an advantage of having friction.
Quite often uses of frction can be seen from how things would be without friction. Without friction, you would not be able to walk, drive a car, or hold objects. Pens and pencils would not work.
Explanation:
The answers is A). Plantas
There must be a balance between the flow of energy into the atmosphere and the flow of energy out of the atmosphere and back to space.<span>After being warmed by incoming solar radiation throughout the day, the Earth emits infrared radiation, which is trapped near the Earth’s surface by carbon dioxide.This radiation is called thermal radiation.</span>
I guess that the endosperm is a unique tissue to the flowering plants. (It helps in their reproduction).