The critical angle for a beam of light passing from water into air is 48.8°. this means that all light rays with an angle of incidence in the water that is greater than 48.8° will be

totally internally reflected

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

i think the answer is a and b

i wish you luck