A. Directions: Write T if the statement is true and F if it is not. Write your answers in your science notebook. 1. The sun is the main source of heat and light. 2. Plants, animals, and humans can survive even without the sun. 3. The effect of the sun's heat and light to the environment causes the changes in temperature. 4. Without the sun the earth will be dark, cold, and lifeless. 5. You can have the shortest shadow at 8:00 am in the morning. 6. An object cast a longer shadow when light rays are slanted. 7. Opaque objects form shadows because they reflect the light.​