Final answer:
To find the standard deviation of a probability distribution when the variance is known, you can take the square root of the variance. In this case, the variance is given as 2.6 grams, so the standard deviation would be the square root of 2.6 grams.
Step-by-step explanation:
To find the standard deviation of a probability distribution when the variance is known, you can take the square root of the variance. In this case, the variance is given as 2.6 grams, so the standard deviation would be the square root of 2.6 grams. The standard deviation can be calculated as follows:
Square root of 2.6 grams = 1.612 grams (rounded to three decimal places).