I believe it’s A..but I’m not quite sure.
the answer you have chosen is correct
The change in energy of the system : -63 J
<h3>Further explanation</h3>
Given
279 J work
216 J heat
Required
The change in energy
Solution
Laws of thermodynamics 1
ΔU=Q+W
Rules :
- receives heat, Q +
- releases heat, Q -
- work is done by a system, W -
- work is done on a system, W +
a gas work on the surrounding : W =-279 J
a gas absorb heat from surrounding : Q = +216 J
Internal energy :
= -279+216
= -63 J
Each element absorbs light at specific wavelengths unique to that atom. When astronomers look at an object's spectrum, they can determine its composition based on these wavelengths.
Not sure if this is 100% but I hope it helps.
Answer:
A conversion factor is a variable that transforms the dimension of one variable into the terms of another variable.
Explanation:
Let be 
and 
two variables with diferent dimensions (units), 
is a conversion if transforms the dimension of one variable into the terms of the other variable. That is:
(1)
Where:
- Input, [input unit]
- Output, [output unit]
- Conversion factor, [output unit] per [input unit]
