List and describe two styles of music composition that developed during the twentieth century.

Soul music, which grew up alongside rock and roll, also developed out of African American gospel, and rhythm and blues traditions. As the century wore on, rhythm and blues boy bands such as New Edition (which could have stayed merely a bubblegum pop band of black youth created for a mainly white audience) took control of their music and helped create the new jack swing movement. A fusion of hip hop and R & B, new jack swing helped laid the groundwork for the next two decades of popular music.

The end of the century saw the birth of hip-hop music and culture. In the mid-1970s in the Bronx, New York DJs began isolating percussion rhythms from songs and talking over and between the songs.

Rap music, with its semi-autobiographical lyrics and deep rhythms were just one more evolution in the blues tradition that had started at the beginning of the century, and one further, enormous transformation in the world of music created and nurtured in the African American community.

tbh, either pop or, i know it's not on the list, but indie/ alternative.

changeable lenses of different focal lengths allow light to enter the camera, which then forms the image on light-sensitive film" is the one among the following statements about working principle behind a basic still camera is true.