The probability distribution of a less risky expected return is more peaked than that of a riskier

Question:

The probability distribution of a less risky expected return is more peaked than that of a riskier return. What shape would the probability distribution be for

(a) Completely certain returns and

(b) Completely uncertain returns?

Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most... Expected Return
The expected return is the profit or loss an investor anticipates on an investment that has known or anticipated rates of return (RoR). It is calculated by multiplying potential outcomes by the chances of them occurring and then totaling these...