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.
Tipping Taxi Drivers. It is polite to tip 10-15% of the taxi fare for black cabs and licensed minicabs in London. However, most people simply round up the fare to the nearest Â£1 and tell the driver to keep the change. If you've had a longer journey and the driver has assisted you with luggage, you may wish to tip a little more, up to Â£5.