JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="size" placeholder="Enter the size in KLOC">
<input type="button" id="enterInfo" Value="Submit"  onclick="calculateBasic(this.form);">

JavaScript

function calculateBasic() {
    var uservalue = Number(document.getElementById("size").value);
    var powerForOrganic = Number(Math.pow(uservalue,1.05));
    var effortForOrganic = Number(2.4 * powerForOrganic);
    var powerTdevOrganic = Number(Math.pow(effortForOrganic,0.38));
    var tdevForOrganic =  Number(2.5 * powerTdevOrganic);
    var averageStaffForOrganic = effortForOrganic / tdevForOrganic;
    var productivityLevelForOrganic = averageStaffForOrganic / effortForOrganic;
    alert( "Effort :" + effortForOrganic + "TDEV :" + tdevForOrganic + "Average Staff :" + averageStaffForOrganic + "Productivity :" + productivityLevelForOrganic);
			
	}

var button = document.getElementById("enterInfo");

button.addEventListener("click", function() {
    calculateBasic();
});