A comet is the loose, icy body with a long, narrow orbit.
Comets are very small solar system body made mainly of ices mixed with smaller amounts of dust and rock. Most comets are not larger than a few kilometers across. The main body of the comet is called the nucleus, and it can contain water, methane, nitrogen and other ices. Their speeds vary depending on their orbits and where they are in it. The closer they are to the sun, the faster they are going.
Answer:
b
Explanation:
it melts yes but it's still water [same element] so there fore it's a physical change
Answer:

Explanation:
<u>Motion in The Plane</u>
When an object is launched in free air with some angle respect to the horizontal, it describes a known parabolic path, comes to a maximum height and finally drops back to the ground level at a certain distance from the launching place.
The movement is split into two components: the horizontal component with constant speed and the vertical component with variable speed, modified by the acceleration of gravity. If we are given the values of
and
as the initial speed and angle, then we have




If we want to know the maximum height reached by the object, we find the value of t when
becomes zero, because the object stops going up and starts going down

Solving for t

Then we replace that value into y, to find the maximum height

Operating and simplifying

We have

The maximum height is


<h2>
Answer: 7020.117 m/s</h2>
Explanation:
The velocity of a satellite describing a circular orbit is<u> constant</u> and defined by the following expression:
(1)
Where:
is the gravity constant
the mass of the massive body around which the satellite is orbiting, in this case, the Earth
.
the radius of the orbit (measured from the center of the planet to the satellite).
This means the radius of the orbit is equal to <u>the sum</u> of the average radius of the Earth
and the altitude of the satellite above the Earth's surface
.
Note this orbital speed, as well as orbital period, does not depend on the mass of the satellite. It depends on the mass of the massive body (the Earth).
Now, rewriting equation (1) with the known values: