Codehs 7.4.6: Gymnastics Mats this the thing is that i cant find solution and need refrence code

Writing a modular program in visual c++. i am new to this and not sure what i am missing. i am getting the following error: baddate. cpp: in function ‘int main()’: baddate. cpp: 50: 3: error: ‘else’ without a previous ‘if’elsehere are the instructions and code: writing a modular program in c++in this lab, you add the input and output statements to a partially completed c++ program. when completed, the user should be able to enter a year, a month, and a day. the program then determines if the date is valid. valid years are those that are greater than 0, valid months include the values 1 through 12, and valid days include the values 1 through 31.notice that variables have been declared for you. write the simulated housekeeping() function that contains the prompts and input statements to retrieve a year, a month, and a day from the user. include the output statements in the simulated endofjob() function. the format of the output is as follows: month/day/year is a valid date. ormonth/day/year is an invalid date. execute the program entering the following date: month = 5, day = 32, year = 2014. record the output of this program. execute the program entering the following date: month = 9, day = 21, year = 2002. record the output of this /* program name: baddate. cppfunction: this program determines if a date entered by the user is valid. input: interactiveoutput: valid date is printed or user is alerted that an invalid date was entered*/#include bool validatedate(int, int, int); using namespace std; int main(){// declare variablesint year; int month; int day; const int min_year = 0, min_month = 1, max_month = 12, min_day = 1, max_day = 31; bool validdate = true; // this is the work of the housekeeping() method// get the year, then the month, then the daycout< < "enter the year"< > year; cout< < "enter the month"< > month; cout< < "enter the day"< > day; // this is the work of the detailloop() method// check to be sure date is validif(year < = min_year) // invalid yearvaliddate = false; else if (month < min_month || month > max_month) // invalid monthvaliddate = false; else if (day < min_day || day > max_day) // invalid dayvaliddate = false; // this is the work of the endofjob() method// test to see if date is valid and output date and whether it is valid or notif(validdate == true); {// output statementcout<

Write a program that displays the following menu: geometry calculator 1. calculate the area of a circle 2. calculate the area of a rectangle 3. calculate the area of a triangle 4. quit enter your choice (1-4): if the user enters 1, the program should ask for the radius of the circle and then display its area. use the following formula: area = ď€(the square of r) use 3.14159 for ď€ and the radius of the circle for r. if the user enters 2, the program should ask for the length and width of the rectangle and then display the rectangle’s area. use the following formula: area = length * width if the user enters 3, the program should ask for the length of the triangle’s base and its height, and then display its area. use the following formula: area = base * height * .5 if the user enters 4, the program should end. input validation: display an error message if the user enters a number outside the range of 1 through 4 when selecting an item from the menu. do not accept negative values for the circle’s radius, the rectangle’s length or width, or the triangle’s base or height. note: if the user enters an improper menu choice (1-4), the program prints "the valid choices are 1 through 4. run the program again and select one of those." if the user enters a negative radius, the program prints "the radius can not be less than zero." if the user enters a negative value for height or base, the program prints "only enter positive values for base and height."

What are "open-loop" and "closed-loop" systems