Astronomers are examining stars in our galaxy and are wondering if they make a sound. The astronomers know that space is a vacuum and sound will not travel far in space but are wondering if the stars themselves are capable of producing sound. Which two questions should the astronomers investigate to help determine if stars make a sound? 1. Are stars made of matter?

2. Does the matter inside stars collide?

3. Are stars transparent or translucent?

4. Do stars convert thermal energy into light energy?

5. Do stars reflect waves?

Which statements help to support your selections above?

6. Reflection is a property of light waves, so if stars reflect waves then they are only capable of producing light waves.

7. If stars convert thermal energy into light energy, then there won’t be any energy available to produce sound waves.

8. Collisions are one way to convert mechanical energy into sound energy, if the matter within them collides, sound waves could be produced.

9. Sound waves require the matter to be transmitted, if stars are made of the matter then they can transmit sound waves.

Select which combination best represents your thinking.
A. 1 and 9 & 2 and 8

B. 1 and 9 & 5 and 6

C. 4 and 7 & 5 and 6

D. 3 and 9 & 4 and 7

the product of the pressure and volume is also constant

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

neutral atoms of elements after calcium contain d electrons. the energy of d orbitals of a particular main shell lies between the energy of the s and p orbitals of the next main shell. for example, electrons in the have energy higher than those in the orbital while lower than those of the orbital.

by the aufbau principle, electrons fill orbitals one at a time, starting from those of the lowest energy. the orbital is therefore filled right after orbitals and before orbitals.  

potassium has electron configuration and calcium . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the and should be highlighted as well.

warm front forms when a moist, warm air mass slides up and over a cold air mass. as the warm air mass rises, it condenses into a broad area of clouds. a warm front brings gentle rain or light snow, followed by warmer, milder weather.

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