Answer: a dark (absorption) line
Explanation:
This is as a result of absorption of electromagnetic a specific wavelength. The pattern followed by such lines is characteristic of specific atoms in the path of radiation.
Not sure this is entirely right but hey why not, right. <span> A planet orbiting a star orbits in an ellipse. Sometimes it's closer to the star and sometimes it's further. When it's closer to the star, the gravity on the planet from the star is stronger, so the planet speeds up. The area the planet sweeps over is equal because when it speeds up the length covered along the orbital path is greater, but it is also closer to the star, and that dimension is decreased. And because of our very intelligently designed and organized universe, these two factors cancel each other out perfectly </span>
<span>Hope I helped in some way!
</span>
Answer:
Acceleration, 
Explanation:
It is given that, two isolated protons are separated by 2 nm. The force due to charged particles is given by :

Force due to mass of proton, 




So, the acceleration of two isolated protons is
. Hence, this is the required solution.
the answer should be "fluids".