Could you please do something for me? (polite form)

toll-free (telephone call)

to inform, to teach, to instruct / to tell

number

teachings, doctrine, lesson

(2channel slang) someone who immediately posts questions instead of doing basic research

(physics, chemistry) atomic number

telephone number

a postal code, a zip code

number (on an athlete's uniform's back); jersey number, uniform number, player number, shirt number