Create a package which includes a function to return a square of a number if it is positive else return an error message to the user.

Create a package circle having the following functions: Area of circle. Circumference of circle. Radius is to be passed as argument to both the functions to calculate values.

Create a package named as INFO which contains procedure that is passed a student’s identification number and return student’s full name and phone number from the student table to the calling program and function, pass a department number to it. ...