The mean time it takes for workers at a factory to insert a delicate bolt into an engine is 15 minutes. The standard deviation of time to insert the bolt is 4.0 minutes and the distribution of time is approximately Normally distributed.

4% of the time, the bolt is inserted in less than which time value? Round to the nearest whole number.

Select one:

a.

4 minutes

b.

8 minutes

c.

19 minutes

d.

23 minutes