hey guys I have a hard question for my college pre help I have done this question but I want to see if you can get it

Is the volume of voids or open space in a rock or unconsolidated material.

Choose the description that best matches each word. write the correct letter in the blank. 1. ostinato a. large, extended composition for chorus and orchestra 2. atonality b. full orchestra 3. musicology c. festive, march-like opening to a play or “semi-opera” 4. concerto d. small group of solo instruments 5. minimalism e. music contrasting a full orchestra and solo instruments 6. art song f. music played under the action to influence the mood 7. strophic form g. a vocal song focusing on artistic expression 8. incidental h. each stanza of a poem is set to the same music 9. oratorio i. repeated musical pattern that provides unity to a piece 10. dissonance j. steady beat; simple harmonies; short, repetitive melody 11. concertino k. harsh, unstable sounding of pitches; harmonic tension 12. tutti l. all 12 tones of chromatic scale, no tonal center 13. entrada m. the historical and scientific study of music

Why are radio observatories located in valleys far away from urban centers? a. to shield them from electromagnetic interference b. to avoid sound pollution c. to avoid disturbing people living in the city d. to shield them from water vapor