five
Every 5 years.
http://www.disabled-world.com/artman/publish/food_pyramid.shtml has a really good picture of the food pyramid. Also, the food pyramid is updated every 5 or so years
every two years
every two years
every two years
It all depends on the size of the pyramid. The ancient greek historian Heroditus (c.450BC) was told by his guide that the Great pyramid at Giza took 100,000 slaves and 20 years to build.
In the UK, the white pages is produced every two years.
No your inventory could deplete and needs to be updated at least once per year
true
true
Every two years
The number of congressional districts per state is determined every 10 years, after the census.