E$2\mathrm{.}1$ Create an entity based on the following scenarios. E$2\mathrm{.}1$a Create an entity based on the following requirement: For each doctor, we will keep track of a DoctorID $($unique$),$ DoctorName, and DoctorYearOfMDGraduation $($year of graduating from medical school$).$E$2\mathrm{.}1$b Create an entity based on the following requirement: For each doctor, we will keep track of a DoctorID $($unique$),$ DoctorName $($composed of first and last name$),$ andDoctorYearOfMDGraduation $($year of graduating from medical school$).$ E$2\mathrm{.}1$c Create an entity based on the following requirement: For each doctor, we will keep track of a DoctorID $($unique$),$ DoctorLicense $($unique$,$ composed of LicenseNo and State$),$ DoctorName, and DoctorYearOfMDGraduation $($year of graduating from medical school$).$E$2\mathrm{.}1$d Create an entity based on the following requirement: For each doctor, we will keep track of a DoctorID $($unique$),$ DoctorName, DoctorYearOfMDGraduation $($year ofgraduating from medical school$),$ and one or more specializations. E$2\mathrm{.}1$e Create an entity based on the following requirement: For each doctor, we will keep track of a DoctorID $($unique$),$ DoctorName, DoctorYearOfMDGraduation $($year of graduating from medical school$),$ and DoctorYearsPracticing $($how many years the doctor has been practicing medicine$).$E$2\mathrm{.}1$f Create an entity based on the following requirement: For each doctor, we will keep track of a DoctorID $($unique$),$ DoctorName, DoctorYearOfMDGraduation $($year of graduating from medical school$),$ and DoctorYearOfPhDGraduation $($year of acquiring a PhD degree; not every doctor has a PhD degree$)$