e1.js

let book1 = {
    title: "Gone with the wind",
    price: 30
}

let book2 = {
    title: "The godfather",
    price: 40
}


// E2. Write a function that takes two parameters: a book and a number (percentage): 
// 2.1 Increases the price of the book with that percentage

function increasePriceByPercentage(book, percentage){
}