Many sources of energy such as nuclear, coal, and oil use a fuel source to turn water into steam. The steam is then used to turn a turbine and generate electricity. Why are these sources not very efficient?

the word that best describes martin luther king jr.'s tone in the video is dignified

martin luther king, jr. was a social activist and baptist minister who played a key role in the american civil rights movement from the mid-1950s until his assassination in 1968. the video shows his manner and attitude having or showing a composed or serious manner that is worthy of respect so dignified is the correct answer