Name, age, weight $($kilogram$)$ and height $($meter$)$ information of $50$ people were entered into a two$-$dimensional A array in a $(50$x$4)$ matrix structure. $($The rows of the matrix define the people, and the columns define the name, age, height and weight information respectively.$)$ Calculating the Body Mass Index $($BMI$=$weight$/($height$*$height$))$ using the column information for each person in matrix A and printing the result to the screen and also printing the result in the list. For the program that allows calculating the average age of $50$ people and printing it on the screen;

A$)$ Draw the flow diagram of the program?

B$)$ Write the program in Python language, paying attention to the spelling rules?