Answer:

Explanation:
The electrostatic potential energy for pair of charge is given by
U=1/4π∈₀×(q₁q₂/r)
Hence for a system of three charges the electrostatic potential energy can be found by adding up the potential energy for all possible pairs or charges.For three equal charges on the corners of an equilateral triangle,the electrostatic potential energy is given by:
U=1/4π∈₀×(q²/r)+1/4π∈₀×(q²/r)+1/4π∈₀×(q²/r)
U=3×1/4π∈₀×(q²/r)
Substitute given values
So
Speed =dist./time
=73.4/5
=14.68 km/hr
To develop this problem it is necessary to apply the concepts related to Wavelength, The relationship between speed, voltage and linear density as well as frequency. By definition the speed as a function of the tension and the linear density is given by

Where,
T = Tension
Linear density
Our data are given by
Tension , T = 70 N
Linear density , 
Amplitude , A = 7 cm = 0.07 m
Period , t = 0.35 s
Replacing our values,



Speed can also be expressed as

Re-arrange to find \lambda

Where,
f = Frequency,
Which is also described in function of the Period as,



Therefore replacing to find 


Therefore the wavelength of the waves created in the string is 3.49m
Answer : (B) Prominence
Explanation :
A large, glittering and gaseous characteristic which is extending outward from the surface of the sun is called <em>Prominence</em>.
<em>Photosphere</em> is one of the layer of sun where the prominence are anchored and then they move into the corona of the sun.
<em>Corona</em> is a region in the surface of the sun which is the constituent of hot ionized gases (plasma).
The prominence consists of colder plasma and this prominence plasma is much more shining and denser as compared to coronal plasma.
Hence, the correct option is (B) Prominence.
Answer:
Sorry I'm wrong The person above is correct.
I tried.