In the Code for HourlyEmployee That Is Derived from Employee,the

In the code for HourlyEmployee that is derived from Employee,the constructor code appears
HourlyEmployee::
HourlyEmployee(string theName,
string theNumber,
double theWageRate,
double theHours
)
: Employee(theName,theNumber),
wageRate(theWageRate),
hours(theHours)
{
// deliberately empty
}
Describe the purpose of the items after the colon (:)in this code.