When heating a substance over a bunsen burner where should the object be placed for the most efficient heating?

for the most efficient heating the object should be placed over the blue flame, above the tip of the flame, where the gases are hottest and there will be no interference with the combustion process, which could result in soot formation.

Explanation:

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