Reflectance values express the percentage of light that is reflected back from a surface, the difference having been absorbed or transmitted by the surface. Reflectances of room surfaces are used in determining coefficient of utilization values for luminaires.
The last three lines show you how to define your own awk function. The format is simple -- type function, then the function name, and then the parameters separated by commas, inside parentheses. After this, a { } code block contains the code that you'd like this function to execute.
Answer: 'AFK' is 'Away from Keyboard'. AFK is used in live chatting to advise people that you will not be responding for the few minutes as you will be away from the computer. AFK is commonly used with a descriptor like afk bio (you are going to the washroom), or afk phone (you are answering a phone call). AFK is a very common expression. AFK can be used in both uppercase and lowercase form. Just remember: typing entire sentences in uppercase is considered rude shouting.