JSFiddle - React, Tailwind, and code Playground

JavaScript

var Benis = {
	a: 23,
	b: 10,
	c: 15,
	d: 5,
	e: 11,
	f: 420,
	g: 7,
	h: 1,
	i: 10
};

var isEven = function(someNumber) {
  return (someNumber % 2 == 0) ? true : false;
};

function changeBenis() {
	for ( i = 0; i < arguments.length; i++ ) {
    if (!isEven(Benis[arguments[i]])) {
			Benis[arguments[i]] = 5;
    }
	}
}

changeBenis('a', 'b', 'c', 'd', 'e', 'f');

console.log(Benis);