Validate that the user age field is between 18 and 100. If valid, set the background of the field to LightGreen and assign true to userAgeValid. Otherwise, set the background to Orange and userAgeValid to false.

function userAgeCheck(event){

 // if age is in range 18 to 100

   // parseInt() converts string into integer

   if( parseInt(userAge.value) >= 18 && parseInt(userAge.value) <= 100 ){

       // set color to light green

       document.body.style.backgroundColor = "green";

       userAgeValid = true;

   }

   else{

       // set color to orange

       document.body.style.backgroundColor = "orange";

       userAgeValid = false;

   }

}

Explanation:

answertrue;