Definition. 1  Lactose intolerance refers to the inability of the body to digest lactose. 2  Lactose is the form of sugar present in milk. The enzyme lactase, which is normally produced by cells lining the small intestine, breaks down lactose into substances that can be absorbed into the bloodstream.
1 Tipping upon drop-off of your car is totally optional and is not done by the majority of drivers. Tip your valet when your car is returned to you from the parking lot.  A tip of $1 to $5 is the typical range, with $2-3 being most common.
You should tip a taxi driver around 10% of your taxi fare. The taxi driver should usually help you load and unload the bags. When you approach the airport, there are porters, called skycaps, who can help with the bags. You should tip them $1 or $2 per bag. You do not tip the flight attendant, employees at the ticket counter, etc. If you need wheelchair assistance, you should tip at least $5 per passenger. At other places like a rental car center, you should generally tip $1 or $2 to whoever helps you with your bags. When you reach the hotel, you should tip $1 or $2 per bag to the bellboy or doorman who handles your bags.