Problem 2-1

A 6937-km² catchment has mean annual precipitation of 485 mm and mean annual flow of 19.7 m³/s. What is the precipitation depth abstracted by the catchment?

Problem 2-2

Given the following intensity-duration data, find the constants a and b of Eq. 2-6.

Intensity (mm/h)	45	20
Duration (h)	1	2

Problem 2-3

Fit a Horton infiltration formula to the following measurements:

Time (h)	f (mm/h)
1	3.5
3	1
∞	0.6

Problem 2-4

The following rainfall distribution was measured during a 12-h storm:

Time (h)	0-2	2-4	4-6	6-8	8-10	10-12
Rainfall Intensity (cm/h)	1.0	2.0	3.0	4.0	2.0	1.0

Runoff depth was 12 cm. Calculate the φ-index for this storm.