In 2015, the social media site "myface" had 400 million active accounts in the US. Each year after that, the number of accounts is predicted to fall by approximately 40 million accounts per year. The same year, "instapic" has 100 million active accounts, however, their membership is predicted to increase by approximately 50 million accounts per year. Part A: During which year will the two companies have the same number of registered accounts?

Part B: During what year is the company "myface" predicted to not have any more registered accounts?