Is an important and necessary step that precedes object-oriented programming?

Consider the following statements: struct nametype{string first; string last; }; struct coursetype{string name; int callnum; int credits; char grade; }; struct studenttype{nametype name; double gpa; coursetype course; }; studenttype student; studenttype classlist[100]; coursetype course; nametype name; mark the following statements as valid or invalid. if a statement is invalid, explain why.a.) student.course.callnum = "csc230"; b.) cin > > student.name; c.) classlist[0] = name; d.) classlist[1].gpa = 3.45; e.) name = classlist[15].name; f.) student.name = name; g.) cout < < classlist[10] < < endl; h.) for (int j = 0; j < 100; j++)classlist[j].name = name; i.) classlist.course.credits = 3; j.) course = studenttype.course;

Write a program that prints the day number of the year, given the date in the form month-day-year. for example, if the input is 1-1-2006, the day number is 1; if the input is 12-25-2006, the day number is 359. the program should check for a leap year. a year is a leap year if it is divisible by 4, but not divisible by 100. for example, 1992 and 2008 are divisible by 4, but not by 100. a year that is divisible by 100 is a leap year if it is also divisible by 400. for example, 1600 and 2000 are divisible by 400. however, 1800 is not a leap year because 1800 is not divisible by 400.

Learning sign language is an example of a(n) learning sign language is an example of a(n)