2. Is Earth currently in danger from any NEOs? Explain how astronomers can determine this risk. PLEASE ANSWER ASAP!!!

There are billions of stars, planets and more over systems like our's solar system inside the universe. But, along with them there are some celestial entities that roam around the space having some mass, as some say that when planets are destroyed or any satellite is broken into smaller pieces the comets or asteroids come into being.
As, they are huge chunks of different elements but mostly they are referred to as the huge rocky objects inside the universe.
Some times due to a larger celestial body's gravitational pull the small objects are attracted towards them. Or more over the small objects are attracted by the planets into there orbits, but to the reason of having larger masses the asteroids or comets onto the surface of the planets. Having the speed of equivalent to thousands of mile per hours in the space. The celestial objects or asteroids may damage the planetary system and cause some of the catastrophic events to ever seen.
While, our planet has some specific parameters to orbit in but a collision with a high speed object may result in the catastrophic events which we might not want to happen any time soon. Because, the speed of the NEO's can bring the dislocation of tectonics plates inside the planet's body. Releasing amount of energy and it will all across the globe depending upon the total amount of momentum,ΔP of the celestial objects.
However, it is believed that the impacts of the NEO's also may result in the disruption of the atmosphere due to rise in the amount of energy inside the planets space