Self-check quiz

1. Fix the error in the following code to use the callback function:

   function addOne(val){
     return val + 1;
   }
   function total(a, b, callback){
     const sum = a + b;
     return callback(sum);
   }
   console.log(total(4, 5, addOne()));
   

2. Write down the result of the following code:

   function checker(val) {
     return new Promise((resolve, reject) => {
       if (val > 5) {
         resolve("Ready");
       } else {
         reject(new Error("Oh no"));
       }
     });
   }
   checker(5)
     .then((data) => {console.log(data); })
     .catch((err) => {console.error(err); });
   

3. What line(s) of code need to be added to the preceding function so that there is always a result after the function runs that ensures the word done is output into the console?
4. Update the below code to make the function return a Promise:

   function myFun() {
     return "Hello";
   }
   myFun().then(
     function(val) { console.log(val); },
     function...