Please fill out and return this sheet after viewing Program #1. If you are unsure of an answer, give your best intelligent guess.

1.  What percent of Earth is covered by H2O?

2.  With respect to the state of matter of H2O, which state is preferred at Earth's distance from the Sun?

3.  What property does H2O have with respect to heat?

4.  What does solid H2O do in liquid H2O?

5.  What event marked the beginning of the Universe?

6.  How long ago did this event probably happen?

7.  What is happening to the size of the Universe?

8.  What gases were abundant in Earth's early atmosphere?

9.  What process led to the accumulation of oxygen in Earth's atmosphere?

10.  How did our Moon likely form?

11.  How did oxygen and other heavier elements found on Earth form?

12.  What are two likely sources of water on Earth?

13.  What are four main elements that make up life?

14.  What does ultraviolet light do to organic compounds?

15.  What is NASA's definition of life?

16.  What are possible environments where life originated?

17.  Without water on Earth, what planet would Earth likely resemble?