Do you believe that the metric system is superior to the previous systems of measure, such as the everyday system used in the United States?
Whatever your answer, what arguments would you use to persuade a person who has a different opinion?

Estimate the number of seconds in a human "lifetime". We'll let you choose the definition of "lifetime."
Do all reasonable choices of "lifetime" give answers that have the same order of magnitude?

Which is a faster speed, 30 mph or 13 meters/second?
Describe in words how you obtained your answer.

Estimate how many 20 cm x 20 cm tiles it would take to tile the floor and three sides of a shower stall. The stall has a square floor, 16 square feet, and five foot walls.