Answer:
There are basically seven spectral types which are used for classifying the stars and it is arranged in the order of increasing temperature from the hottest temperature to the coldest division are: O, B, A, F, G, K, and M. These categories are basically divided into the sub category in the spectral where O is the hottest type and M is the coldest type.
Answer:
Energy loss per minute will be 
Explanation:
We have given the star produces power of 
We know that 1 W = 1 J/sec
So 
Given time = 1 minute = 60 sec
So the energy loss per minute 
We multiply with 60 we have to calculate energy loss per minute
(20 N)/(2 m²) = (20/2) N/m² = 10 Pa
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The pascal (Pa) is the derived SI unit of pressure equal to 1 N/m².
<span>It takes heat to make something evaporate, so it takes heat from your arm. Alcohol easily evaporates at room temperature, so it feels cool. This is also why you feel cool when getting out of the pool. The water on your skin evaporates.
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