How to Master the ielts

203
Q53 
(seventh paragraph) 
efficient
. The answer is 
efficient
because 
‘more 
efficient’
in the summary following on from the words ‘though expensive’ 
can be linked to 
‘twice as efficient’
in the passage.
Reading Passage 
2
. Taking soundings
Q54
Paragraph 
B. an example of sound being used other than for naviga-
tion and location of prey
. 
Communication
is the other use, as described 
in the first sentence of paragraph B.
Q55 
Paragraph 
A. examples of mammals other than whales and dolphins 
that use echolation
. Bats are the other mammal as described in the first 
sentence of passage A.
Q56 
Paragraph 
D. how man’s behaviour has increased the number of 
whales being stranded
. ‘
high-power military sonar
might disorientate or 
harm whales, and that it is 
responsible for 
the mass
strandings
seen on 
beaches’.
Q57 
Paragraph 
E. an example of whales living in a community
. ‘Whales are 
social animals
 that swim in groups known as “pods”
.’
Q58 
Paragraph 
B. why people cannot hear whale song
. 
‘Low frequency 
vocalizations
,
 
in the form of grunts and moans are
 inaudible to the human 
ear
,
 
but form a pattern or song
’
. (Q58 distracter: the clicks, known as 
ultrasound, consist of high pitch (frequency) sound waves, 
‘well above 
the range of the human ear, and distinct from the low pitched whale song’
).