There are four activities on the critical path, and they have standard deviations of 1, 2, 4, and 2 days. The standard deviation of the critical path is: A. 3.
B. 5.
C. 9.
D. 16.
E. 25.

There are four activities on the critical path, and they have standard deviations of 1, 2, 4, and 2 days. The standard deviation of the critical path is:

C. 9.

Explanation:

The implication is that the standard deviation of the critical path is the sum of the standard deviations of the four activities on the critical path.  This sums to 9 days (1 + 2 + 4 + 2), implying that the critical path varies from the mean days of critical path activities by 9 days plus or minus.

in 2001, dell computer became the world’s largest personal computer vendor, continuing to

gain market share and post profits in an industry struggling with slumping sales and billions of

dollars in losses. dell sells 90% of its pcs directly to the final customer, largely bypassing the

reseller channel that accounts for most of the world’s pc sales. this direct customer relationship

is the key to dell’s business model, and provides distinct advantages over the indirect sales

model. dell’s direct relationship with the customer allows it to tailor its offerings to customer

needs, offer add-on products and services, and use the internet to offer a variety of customer

services. in addition, dell’s pcs are built to customers’ specifications upon receipt of an order,

giving dell additional advantages over indirect pc vendors who must try to forecast demand and

ship products based on those forecasts. dell’s direct sales and build-to-order model has achieved

superior performance in the pc industry in terms of inventory turnover, reduced overhead, cash

conversion, and return on investment (kraemer, et al., 2000).

explanation: