So, the first quartile means that you want to know what the 25th percentile is for the given mean and the third quartile is the 75th percentile. Using your z table, look up the z value for the 25th percentile for part a. That is, the value 0.25 corresponds to what z value? It should be about -0.675. Do you know how to find this? Then just use this equation:

\(\displaystyle z=\frac{x - \mu}{\sigma}\)

You're solving for x here given mu and sigma and looking up z in the table.

\(\displaystyle x = z\sigma + \mu\)

In order to do part b, look up the z value for the 75th percentile and re-solve.

You should know that the first quartile should be a very low score and the 3rd quartile should be much larger. Just to get a sense if your answer is correct.