Exercise 1

Spec: Write a loop that displays (on the console) the powers of 2 (i.e., 2 to the n-th power) for all numbers (n) ranging from 0 to 20. Your output should be displayed in user-friendly text, i.e., "2 to the power of 8 is 256."

Code:

                    for (i = 0; i < 21; i++)
                    {   
                        console.log(`2 to the power of ${i} is ${2 ** i}`);
                    }
                

Exercise 2

Spec: Write a function that implements the Pythagorean theorem and returns the length of the hypotenuse of a right triangle using the lengths of the sides, which are to be passed in to the function as arguments.

Implementation:

function pythagorianHelper(a, b)
{
    return Math.sqrt(a**2 + b**2);
}  
// Test with some famous: Pythagorean triples:
console.log(pythagorianHelper(3, 4));
console.log(pythagorianHelper(12, 5));
                

Exercise 3

Spec: Write a function that can be used to test whether a number is even or odd, and call this function on at least one even number and one odd number to demonstrate that it works properly. The function should return a value of true if the number is even and false if the number is odd.

Implementation:

function parityTester(x)
{
    if ((x % 2) == 0) return true;
    return false;
}

console.log(parityTester(1))
console.log(parityTester(13))
console.log(parityTester(16))
console.log(parityTester(-16))
console.log(parityTester(-9))
                

Exercise 4

Spec: Write a function that converts Degree-Minute-Second (DMS) coordinates to decimal degrees. The function should accept degrees, minutes, and seconds as three separate arguments.

Implementation:

function degreeConverter(d, m, s)
{
    // 3600 seconds in a degree:
    let decimalSeconds = s / 3600;
    let decimalMinutes = m / 60;
    
    return decimalSeconds + decimalMinutes + d;
}

console.log(degreeConverter(-55, 5, 34));
console.log(degreeConverter(0, 30, 0)); // Should return 0.5
console.log(degreeConverter(0, 0, 360)); //Improper seconds
                

Exercise 5

Spec: Write a statement that changes the HTML content of a <div> tag.

Implementation:

Suppose your div tag has an id attribute of "myDiv1":

<div id="myDiv1">Original text, boring :(</div>
                

You could include the following JavaScript to change the displayed text:

document.getElementById("myDiv1").innerHTML = "New text, hooray!";