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The "Mark and Measure Exercise" Lesson is part of the full, Mastering Chrome Developer Tools v2 course featured in this preview video. Here's what you'd learn in this lesson:

In this exercise, students need to determine how long an API call takes to complete.

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Transcript from the "Mark and Measure Exercise" Lesson

[00:00:00]
>> Jon Kuperman: For this exercise, we're just doing a mark and measure, right? So we've got this mark and measure js file. So let me open my dev tools. Got mark-and-measure.js. It really just waits for the window to load, runs a random function. That function just hits that API that we hit earlier, JSONs the results and then console.logs all of them, right?

[00:00:18] [LAUGH] So if we look in the console, we see these things. So what we wanna know is how long did this take to go? And so I would encourage you to do it two different ways. One, put some date times in this file and calculate them like we did in the slides and then do a performance mark.

[00:00:33] You should see the same calculation, but also when you do it with performance mark, check the performance tab, cuz you should be able to see a really cool UI for that. So yeah, we'll take a little break. And then we'll come back, and we'll do it all together.