At a traffic intersection, cars and buses arrive randomly according to independent Poisson processes at an average rate of 4 vehicles per hour and 2 vehicles per hour, respectively. The probability of observing at least 2 vehicles in 30 minutes is __________. (round off to two decimal places)
The vehicle count obtained in every 10 minute interval of a traffic volume survey done in peak one hour is given below.
| Time Interval (in minutes) | Vehicle Count |
|---|---|
| 0 - 10 | 10 |
| 10 - 20 | 11 |
| 20 - 30 | 12 |
| 30 - 40 | 15 |
| 40 - 50 | 13 |
| 50 - 60 | 11 |
The peak hour factor (PHF) for 10 minute sub-interval is _____________. (round off to one decimal place)
For the dual-wheel carrying assembly shown in the figure, P is the load on each wheel, a is the radius of the contact area of the wheel, s is the spacing between the wheels, and d is the clear distance between the wheels. Assuming that the ground is an elastic, homogenous, and isotropic half space, the ratio of Equivalent Single Wheel Load (ESWL) at depth z = d/2 to the ESWL at depth z = 2s is __________. (round off to one decimal place)
(Consider the influence angle to be 45$$^\circ$$ for the linear dispersion of stress with depth)
You should __________ when to say __________.