What is a control group? (A) A group that changes the variable
(B) The group that applies the variable
(C) The group that tests the variable
(D) A test group where the variable is not changed or applied

b would be the answer

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

0.11 m/s and 0.28 m/s should be correct