Answer:
C. 3
Explanation:
This is usually the required amount.
Answer:
none. there are none. well at least not 40. you got bad, cab, bac, ab, cad,
Explanation:
Answer:
Dorothy Vaughan was an American computer programmer and mathematician who made significant contributions to the early U.S. space program. She was also the first Black American supervisor at NASA, a role she would continue to hold up to and beyond its merger with NASA.
Hope this is write I did a lot of reserch!