This year is the 40th year of federal observation for Martin Luther King Jr. Day a day designated to encourage all citizens to volunteer and improve their communities.Here's what is open and closed for the federal holiday:GOVER NMENT BUILDINGSGovernment offices, post offices, courts and schools are closed in observance of the holiday. This also includes community services like libraries.MAIL AND DELIVERYThe U.S. Postal Service will not deliver mail on Monday. UPS typically does not deliver on the holiday, but FedEx generally still does offer delivery services.BANKS AND STOCK MARKETU.S. stock markets and banks are closed on Monday.OTHERThe vast majority of retailers will be open, but check your local stores for exact hours.The National Park Service removed Martin Luther King Jr. Day from its list of free admission days this year, according to the agency's website. However, some states, like California, have made it a free entry day for state parks in response. ...read more read less