So here it says use the method discussed above determine the answer to the following question. So here we have 7.5×10-3 taken to the fifth power times the 4th root of 8.6×1021, and we're going to see what our answer is.
Now what you should do is you should do (7.5×10-3) and then you raise it to the fifth power. If you do that correctly, what you should get initially is 2.37305×10-11. Check to see you got the same answer that I did times. Remember this here is the same thing as saying 8.6×1021 in parentheses taken to the one fourth power. Remember 4th root is the same thing as one fourth power.
So if we take this to the one fourth power, what you should get at the end is 304526. Then we multiply those two numbers together. And remember here when you're multiplying or dividing, the number of significant figures is the lowest, right? So this coefficient here has two sig figs. That this coefficient here has two sig figs. Or answer at the end must have two sig figs.
So what you get here is 7.2×10-6. So input that answer, input these numbers into your calculator and see if you get the same answer that I got at the end. Again, you may be able to write things down correctly on paper, but if you're struggling and punching it into your calculator then you won't ever get the correct answer. So keep practicing when it comes to inputting these values into whatever calculator model that you're using.