Pull ups exercise / grow which muscle in the body?

If an online school program (i.e k12, ecot) assigns me a computer, would it be ok to use social media on it? would i get in trouble? i am not really sure from reading their terms and such.

Why would one lymph node in the neck be swollen and not the other? what causes them to swell?

How much do the tanakas spend on health insurance premiums each year