Answer:
Explanation:
Given
Initial Intensity of light is S
when an un-polarized light is Passed through a Polarizer then its intensity reduced to half.
When it is passed through a second Polarizer with its transmission axis 

here 


When it is passed through third Polarizer with its axis
to first but
to second thus 



When middle sheet is absent then Final Intensity will be zero
The work done by the heat engine is 40 kCal.
The given parameters;
- input heat of the engine, Q₁ = 70 kCal
- output heat of the engine, Q₂ = 30 kCal
To find:
- the work done by the heat engine
The work done by the heat engine is the change in the heat energy of the engine;
W = Q₂ - Q₁
Substitute the given parameters and solve work done (W)
W = 70 kCal - 30 kal
W = 40 kCal
Thus, the work done by the heat engine is 40 kCal.
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2. Groups
3.Ion
4.NonPolar
5.Metallic Bond
6.Make up most of the atom's mass
7.Atomic Number
8.Seven