I am new to stats and have an assignment due in two days.
I can only explain it by writing out the problem. Not sure how to begin solving.

The mean of the annual return for common stocks during a 67 year period was 15.4% and the standard deviation was 5.5%.
During the same time span, the mean of the annual return for long term government bonds was 5.5% and the standard deviation was 6 %.
Both are bell shaped and symmetric.
How do I find the probability that the return for common stocks will be greater than 8%
How do I find the probability that the return for common stocks will be greater than 20%

Not sure how to start. HELP PlEASE!