The standard deviation of a critical path is computed by:
a. taking the sum of the standard deviations of all activities that are on the critical path.
b. taking the square root of the sum of the variances of all activities that are on the critical path.
c. taking the standard deviation of the task that takes the longest to complete taking the sum of standard deviations of all tasks in the project
d. None of the above

Adouble-strand no. 60 roller chain is used to transmit power between a 13-tooth driving sprocket rotating at 300 rev/min and a 52-tooth driven sprocket. a) what is the allowable horsepower of this drive? b) estimate the center-to-center distance if the chain length is 82 pitches. c) estimate the torque and bending force on the driving shaft by the chain if the actual horsepower transmitted is 30 percent less than the corrected (allowable) power.