a _ is an explanation that unifies the findings of many experiments, and it can be changed when new experimental results need to be explained

That's a pretty good intuitive definition of a theory .

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