Source: US Census. The median household income in the US is $50,502. This is some extremely useful data given that it is exploring over 114 million US households. If you want to know how most Americans are living this is a good figure to base your assumptions.
The myth that you have to wait 30 minutes or even an hour until you can swim after eating has been conventional wisdom for some time. The simple fact is, however, that swimming on a full stomach does not significantly impact your ability to swim.
You should wait until the skin has completely healed before swimming, which is usually about 2 weeks, but it varies from person to person. You should keep it out of direct sunlight forever essentially (suncream). If you don't, the colors can bleed, and some, especially light ones, can almost disappear all together.