Distillation is a process in many laboratories for the purpose of
separating and/or purifying components of a liquid mixture. The distillation apparatus used consists of
three major parts: <span>distillation flask - to heat the mixture and volatilize the components,
a condenser to cool the vapors back to liquid state, and a collection vessel. The apparatus is typically made of glass and
therefore subject to breakage.</span> <span>All components of the distillation apparatus
should be protected to a stable stand or rack to avoid it from falling over.</span>
Answer:

Explanation:
We are given that



We have to find the angle of refraction.
By Snell's law

Substitute the values




Hence, the angle mad by refracted ray in to the glass with normal=
As we know that two charges exert force on each other when they are placed near to each other
The force between two charges is given as

here we know that
= two different point charges
r = distance between two point charges
also we know that two similar charges always repel each other while two opposite charges always attract each other
so here correct answer would be
<em>A. A positive and negative charge attract each other.</em>
Answer:
1. A ruler is a common instrument used for measuring the length of small objects
2. The acceleration due to gravity at the surface of Earth is about 9.8 metres per second per second.