Explain how different combinations of a planetary mass and orbital angle can create similar velocity graphs?

Its in the national history museum and you can't se the original because its locked away in a vault 

I’m confused ///: : : :

Historians are researchers of the past or people who understand the history of people. with this field, they must possess qualities such as being unbiased, patient, efficient reader, has a knack for logic and critical thinking and reasoning, disciplined, open-minded, resourceful, with good analytical ability, good reasoning skills and problem solving!