Answer:
Hey, what's up?
"What's up" can be considered to be slang.
Thank you very much.
This sentence does not use slang; it is a very professional sentence.
I'm just going to chill today.
The word "chill" is slang.
That's a sweet thing to say.
This sentence does not contain any slang words.
Drew got busted.
"Busted" is a slang word.
Therefore, the 3 sentences with slang are:
Hey, what's up, I'm just going to chill today and Drew got busted.
