7.A hiker shouts toward a vertical cliff that is 685 m away. The echo is heard 4.0 s later. (a) What is the sound wave’s speed (v)? (b) The wavelength (λ) of the sound is 0.75 m. What is the wave’s frequency (f)? (c) What is the wave’s period (T)?

One form of energy can be another type of energy. a. created to form b. transformed into c. destroyed and then created to form

The energy equivalent of the rest mass of an electron is

4. now look at the green lines you created by connecting the three boiling point data points and the three melting point data points. for each of these lines, describe any trends you see. 5. locate the elements on your periodic table that you circled in green on your graph. what term or description would you use to identify these elements with respect to the periodic table? 7. using the room temperature line (orange line) and your periodic table, make lists that identify the state of matter (gas, liquid, or solid) in which each element you plotted exists at room temperature. explain your answers.