Someone please explain me this​

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."

Fast answer i need for apex ! smartphones should be banned from the classroom in public schools so that students cannot cheat on test so easily? which is an example of a counter argument to the thesis above? a.the classroom is a place for learning not for making phone calls b. smartphones are useful learning tools in the modern classroom c.banning smartphones will not students pay attention to teachers any better d. banning smartphones would decreased incidents of theft

When analyzing data sets, such as data for human heights or for human weights, a common step is to adjust the data. this can be done by normalizing to values between 0 and 1, or throwing away outliers. for this program, adjust the values by subtracting the smallest value from all the values. the input begins with an integer indicating the number of integers that follow. ex: if the input is 5 30 50 10 70 65, the output is: 20 40 0 60 55