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This practice session covers basic JavaScript functions.

It's a great followup to the fifth part of the JavaScript Basics course.

If you haven't taken that yet, and find this practice session too difficult,

then go through the first five parts of that course first.

I've added a link in the teacher's notes below.

For this practice session, you'll write four functions.

Call those functions and output the results to the console.

It's pretty simple but combines the basics of creating and

using JavaScript functions.

I've attached a workspace to this video which includes some starter files and

instructions.

Open up the workspace and open up the geometry.js file.

You'll see six instructions listed as JavaScript comments.

Here's what you should do.

First attach the JavaScript file to the index.html file.

After all, the program won't work at all unless the web page loads it.

Next create a function that calculates the area of a rectangle.

To calculate the area of a rectangle, you multiply the width by the height.

So this function needs to accept two arguments,

do some math, then return the results back.

Then you'll create another function to calculate the volume

of a rectangular prism.

Also known as a box.

For that, you multiply the width by the height by the length.

This function should return the volume.

Now the next two functions involve calculating the area of a circle and

the volume of a sphere.

These both require using the JavaScript math object to get the value of pi.

And to use a method that lets you raise the number to a certain power.

For example x to the second power or x squared.

Now I didn't cover those in JavaScript basics course, so

you'll need to do a bit of research to figure out how to use them.

I've included links in the teacher's notes below.

Okay so if you have the radius of a circle to calculate the area of a circle,

you take pi times the radius squared.

Squared is also refered as the second power or to the second power.

So the function will receive a radius value and return the area.

The last function will calculate the volume of a sphere.

To do that you multiply four thirds by pi, by the radius cubed or

the radius to the third power.

Okay now finally you'll add four lines to log out

the results of your function to the JavaScript console.

It's not super exciting to look at, but this is what your output should look like,

something like this.

Now if you wanna do some quick study before tackling this practice session.

In the teacher's notes look for

links to videos that can help you solve this challenge.

But if you're ready, go for it.

Program your solution and I'll show you my solution in the next video.