The three commonly used alpha levels are p=01, p=05, and p=10

a. Explain what each level means.
b. Which one of the three is more frequently used in research?

2 answers

You may find what you need in one of these sites.

http://www.google.com/search?source=ig&hl=en&rlz=1G1GGLQ_ENUS362&q=psychology+alpha+levels+
P = probability that the results would occur solely on the basis of chance (alpha error). This is the likelihood of rejecting the null hypothesis, when the null hypothesis is really true.

Check various research projects to get an idea of which level of significance is used. However, I would be on .05. (By the way, the decimal point does make a difference.)