__________, also called "negative euthanasia," involves the practice in which no heroic measures are taken to preserve life.

The greatest amount of progesterone is secreted during the week after:

A) ovulation B) delivery of a baby C) breast feeding D) none of the above

________ is a colorless, odorless gas that is encountered as a component of liquefied petroleum gas.

A) Oxygen B) Ethylene C) Propane D) Hydrogen