Jane goodall spent years with the chimpanzees of gombe. sitting quietly for hours, she watched the animals closely and took notes about their behavior.

Jane Goodall was making observations on chimpanzees.

Explanation:  

Jane Goodall spent years with the chimpanzees of Gombe. It all started when she found a chimp who was hungry and wonderfully used a twig of the branch to take the termites of the tree and feed on it. Goodall was fascinating to see a chimp think and behave like a human.

She observed the animal so closely and took note of each behavior. She was so passionate about the chimps that she overcame all the hurdles to find out the redefined mankind.

d is the answer

sorry if its wrong!

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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