I have seen many sample tests from Invitational along with the answer keys. While some of the questions relating to statistical data pertaining to some year and date may be hard to challenge(depending on where the information of such statistical data are obtained from), but those that are related to calculation, it can be easily verified and double checked. Don't take the answer key as the final doctrine as many were just wrong.

Here's are 2 example such wrong answer. Do your own calculation...not all answer keys are correct...and to make it more challenging. On the Potential Energy calculation, there are follow up questions that rely on the answer from the calculation. So if you start of wrong, then everything else will be wrong as well.

What's more important is that for those who taken these tests, what happen if they answer correctly?....they got mark WRONG???!!!