solving problem 1:

[m4saleh]

(The Fortune Teller)

var numberChildren = 20;
var partnerName = "Mohammed";
var geographicLocation = "Riyadh";
var jobTitle = "Computer Engineering";

solving problem 2:
(The Age Calculator)

var thisYears = 2019;
var YourBirthYear = 1999;
var yourAge = thisYears - YourBirthYear;
console.log(yourAge);

solving problem 3:
(The Lifetime Supply Calculator)

var yourCurrentAge = 24;
var maximumAge = 60;
var estimatedAmountPerDay = 30;
var thisYears = 2019;
var remainingOld = maximumAge - yourCurrentAge ;
var remainingAmount = remainingOld * estimatedAmountPerDay ;

console.log("You will need " + remainingAmount +
" last you until the ripe old age of " + maximumAge );

solving problem 4:
(The Geometrizer)

var radius = 5;
var circleCircumference = radius * 3.14 +" cm";
var circleArea = (radius * radius) * 3.14 +" m2";
console.log("The circumference is " + circleCircumference);
console.log("The area is " + circleArea);

solving problem 5:
(The Temperature Converter)

var celsiusTemperature = 26;
var fahrenheitTemperature = (celsiusTemperature * 1.8) + 32;
console.log( celsiusTemperature + " °C " + " is " + fahrenheitTemperature + " °F " );

var celsius = (fahrenheitTemperature - 32)/ 1.8;
console.log( fahrenheitTemperature + " °F "+ " is " + celsius + " °C " );