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1 Figure 1 shows a stream flowing near a fertiliser factory.
The factory burns coal as a source of energy.
The factory releases waste into the stream and sulfur dioxide into the air.
Samples of water were taken at five points, A, B, C, D and E, as shown on Figure 1.
direction of water as it
flows downstream
fertiliser factory
D
E
C
A B
Figure 1
Figure 2 shows the oxygen concentration in the water at the five points along
the stream.
oxygen concentration
point along stream
(ppm)
A 1.5
B 2.7
C 3.4
D 4.4
E 4.5
Figure 2
2
*P72629A0228*
, (a) (i) Calculate how many times greater the oxygen concentration is at point E than
at point A.
(1)
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............................................... times greater
(ii) State how the oxygen concentration changes from point A to point E.
(1)
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