What is ten to the power of negative seven written as a number?

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Find a number such that if you add 8 and divide the result by 4 you will get the same answer as if you subtracted 3 from the original number and divided by 2

Chandler was a caretaker at the state zoo. he noticed that the number of animals adopted by the zoo increased at a constant rate every year since 2010. which of the following graphs shows the slowest rate at which the animals in the zoo were adopted?