It means the scientific study of sight and the behavior of light, or the properties of transmission and deflection of other forms of radiation
I would love to answer this question but it looks like you need to attach a passage to answer this question. Btw the other answer that other person gave you was just to get points there is no file.
Answer:
Even in the not-officially-segregated North, there was often a wide gulf between the color-blindness of the American dream and the racial discrimination in daily life, which, early in their lives, crushed the aspirations and dashed the hopes of promising young black Americans. In this story (published in 1941), celebrated poet, novelist, and playwright Langston Hughes (1902–67) describes such an incident in the life of a talented and proud American high school student, Nancy Lee Johnso
