Happy Birthday is a mixtape  that features a rapper who earned what in 2010?
Happy Birthday (mixtape):  "Happy Birthday" features British rappers Chipmunk, Giggs, Wretch 32, G-Frsh, Tinchy Stryder and Krept and Konan, including a variety of American rappers; Soulja Boy, J. Cole and Big Sean, along with Wiz Khalifa, Pusha T and Jim Jones on the "Till I'm Gone" remix (originally released on August 29, 2011).
i don't know