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<html><body><h1>JavaScript Objects</h1><h2>The Object.isExtensible() Method</h2><p id="demo"></p><script>// Create Objectconst person = {firstName:"John", lastName:"Doe"};// Prevent ExtensionsObject.preventExtensions(person);// This will return falselet answer = Object.isExtensible(person)document.getElementById("demo").innerHTML =answer;</script></body></html>