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the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their
individual course preparation. If you are a student using this Manual, you are using it without permission.

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1-5 Repeat Prob. 1-3 for peak demand

Given: 280 metered houses, AWWA average

Solution:

a. From text: peak hour = 5.3(avg. day)

(5.3)(280 houses)(1,320 L · d-1 · house-1) = 1.96 x 106 or 2 x 106 L · d-1 at the peak hour

1-6 Water lost (in liters) in one year

Given: One drop per second, 0.150 mL per drop

Solution:

(0.150 mL · s-1)(86,400 s · d-1)(365 d · y-1)(1 x 10-3 L · mL-1) = 4,730 L · y-1

1-7 Monthly cost of not repairing valve

Given: Valves deliver 130.0 L · min-1, Water cost = \$0.45 per cubic meter

Solution:

a. Assuming 30 d · mo-1

(130.0 L · min-1)(1440 min · d-1)(30 d · mo-1)(1 x 10-3 m3 · L-1) = 5,616 m3 · mo-1

(5,616 m3 · mo-1)(\$0.45 m-3) = \$2,527.20 or \$2,530 mo-1

1-8 Value of water lost

Given: Year 2000 data from Prob. 1-2, 15% water loss, cost of water = \$0.45 m-3

Solution:

a. Amount of water lost

(1.6 x 108 m3 · d-1)(0.15) = 2.4 x 107 m3 · d-1

b. Value

(2.4 x 107 m3 · d-1)(\$0.45 m-3) = \$1.08 x 107 or \$1.1 x 107 d-1

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may be displayed, reproduced or distributed in any form or by any means, without the prior written permission of
the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their
individual course preparation. If you are a student using this Manual, you are using it without permission.

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CHAPTER 1
DISCUSSION QUESTIONS

1-1 Defining hypothesis, theory, law

Given: Explanation to a non-scientist

Solution:

A hypothesis is a statement that under certain circumstances certain phenomena may be
observed.

A set of generalizations that may be tied together under a given set of assumptions are
formulated as a theory.

Theories that have gained acceptance over a long period of time are known as laws.

1-2 Per capita water consumption

Given: requirements to determine water consumption for local college or university

Solution:

Data to be collected include population served and the average water use for the
institution.

1-3 Internet search

Given: Clean Air Act and requirements to identify subject matter of Title II, chemical
name of first hazardous air pollutant under Title III, last year that carbon tetrachloride can
be produced.

Solution: