Answer:
Distance cover in 2 hour = 6 kilometer
Explanation:
Given equation:
x = 2t - 10
where
x = kilometer
t = hour
Find:
Distance cover in 2 hour
Computation:
T = 2
So,
x = 2t - 10
x = 2(2) - 10
x = 4 - 10
x = -6
Distance cover in 2 hour = 6 kilometer
First we find the energy level with the following formula, where a is the energy level, n1 is the final energy level, n2 is the starting energy level and r is Rydberg's constant in Joules

We insert the values


The wavelength is found with this formula, where h is Planck's constant and c is the speed of light

Finally we insert the values

Which is the same as 93.8 nm
I do not know what the school expects as an answer, but advantage of reflecting telescopes is that there is only one major reflecting surface, so it is quite easy to create a 6 or 8 inch telescope by an amateur, after adding on a prism and an eyepiece. (a microscope eyepiece could be used).
MY answer would be "easier to build". (it still takes tens of hours to grind and polish the single plane surface to a parabolic surface).
Electromagnetic waves all have the same velocity in the same medium. However, since frequencies vary widely, so do wavelengths.
The answer to this is A. this is because, refraction with a light or sound wave changing its direction involve propagation,(in which propagation is the change in direction of a light or sound wave)
Answer:
the air has to be unstable as well as it needs to be moved upwards.
Explanation:
it needs to be moved upwards and also needs to have unstable air.