A classmate asks you to check their answer to this problem:

Simplify: a3b5a2b−3
They got a6b−15
as their final answer. Are they correct?

Responses

No, the answer is not correct. When the bases are being multiplied, you need to multiply the exponents.
No, the answer is not correct. When the bases are being multiplied, you need to multiply the exponents.

No, the answer is not correct. When the bases are being multiplied, you need to add the exponents.
No, the answer is not correct. When the bases are being multiplied, you need to add the exponents.

Yes, this is the correct answer.
Yes, this is the correct answer.

No, there should not be negative exponents. The final answer should be a6b15

No, there should not be negative exponents. The final answer should be a6b15.