Assume that an investment is forecast to produce the following returns:

a 20% probability of a 10% return;

a 50% probability of a 17% return;

a 30% probability of a 23% return.

The standard deviation of return for this investment is Blank 1. Calculate the answer by read surrounding text. %. Round to the nearest 0.01% (drop the % symbol). E.g., if your answer is 3.11%, record it as 3.11.