An activity supervisor makes the following estimates about the probability distribution of her activity duration. Optimi

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An activity supervisor makes the following estimates about the
probability distribution of her activity duration.
Optimistic duration = 10 days
Most likely duration = 16 days
Pessimistic duration = 25 days
1) What estimate of the expected (mean) activity duration should
the project manager make?
< 15
>= 15 and < 20
>= 20 and < 25
> 25
2) What estimate of the standard deviation of the activity
duration should the project manager make?
< 1
>= 1 and < 2
>= 2 and < 3
>= 3