figured out about does the math add up. mj le mj lee on whether it will warn the critics. >> reporter: elizabeth warren finally releasing her own plan on how to pay for medicare for all. the presidential candidate answering one question she's repeatedly dodged for weeks. >> will you raise taxes on the middle class for -- to pay for it, yes or no? >> costs will go up for the wealth beyond for big corporations and for hard-working middle class families costs will go down. >> we heard it tonight. a yes or no question that didn't get a yes or no answer. >> saying her answer is no. >> i have a plan that shows how we can have medicare for all without raising taxes one cent on middle class families. >> reporter: her price tag, $20.5 trillion of new federal spending over ten years. the senator laying out the math