Everything starts from spectroscopy. Astronomers only have concentrated information at wavelengths that are emitted from the stars. What they do with this information is to obtain the frequency range of the stars and through spectroscopes they are responsible for dividing the radiation beams and determining the coincidence with the emission of those same waves, of chemical elements. From these observation techniques it is possible to obtain the composition and according to the color, obtaining characteristics such as temperature. The spectrum of stars consists of dark and bright lines called Fraunhofer lines. This spectrum is compared to the spectrum of different elements to find the composition of the stars. This is possible because the elements emit or absorb only specific wavelengths.
Answer: A method of classifying stars by their temperatures and compositions.
Explanation:
Answer:
See below.
Explanation:
Cubit is a unit of length based on the length of the forearm from the elbow to the tip of the middle finger and usually equal to about 18 inches (46 centimeters).
It is an ancient unit of length used in ancient Egypt and is also known as "ancient Egyptian royal cubit."
Other similar units of measurements are displayed in the image below. Thanks!
The answer is Concave lenses
Answer:

Explanation:
<u>Horizontal Launch
</u>
It happens when an object is launched with an angle of zero respect to the horizontal reference. It's characteristics are:
- The horizontal speed is constant and equal to the initial speed

- The vertical speed is zero at launch time, but increases as the object starts to fall
- The height of the object gradually decreases until it hits the ground
- The horizontal distance where the object lands is called the range
We have the following formulas




Where
is the initial horizontal speed,
is the vertical speed, t is the time, g is the acceleration of gravity, x is the horizontal distance, and y is the height.
If we know the initial height of the object, we can compute the time it takes to hit the ground by using

Rearranging and solving for t



We then replace this value in

To get



The initial speed depends on the initial height y=32.5 m, the range x=107.6 m and g=9.8 m/s^2. Computing 

The launch velocity is
