B. so light can shine through it from below.
Well the chocolate bar may melt at the heat of the machine but why is there a chocolate bar there in the first place is my question xD
Answer:
Liquid's index of refraction, n₁ = 1.27
Explanation:
It is given that,
The critical angle for a liquid in air is, 
We have to find the refractive index of the liquid. Critical angle of a liquid is defined as the angle of incidence in denser medium for which the angle of refraction is 90°.
Using Snell's law as :

Here, 

Where
n₂ = Refractive index of air = 1
n₁ = refractive index of liquid
So,


n₁ = 1.269
or n₁ = 1.27
Hence, the refractive index of liquid is 1.27
1.could be anything... make sure there is safety nets below in case of an accident?
2. F1 car is more stable because the center of gravity is lower than the double deckers center of gravity
3. To find the mass of an object just put it on the scale, to find the volume put the object in a marked beaker to measure the water displacement which is the volume