[CR][bats sound] HSPA posts

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[CR][bats sound] HSPA posts

by HSPA » Sun Apr 17, 2011 3:56 am
Bats emit sounds and generally use the echoes of these sounds highly efficently to detect, locate and catch their preys. However, it is claimed that the characteristic efficiency of this process is reduced by moths able to hear the sounds emitted by insect-eating bats.
Which of the following statements if true, best supports the claim above?
A. Those moths cannot hear the sounds emitted by insect-eating bats live longer on the average than those that can hear such sounds when both kinds of moth are in an environment continuously free of such bats.

B. Those moths that cannot hear the sounds emitted by insect-eating bats are among the species of insects that are most liekly to be caught by such bats.

C. When a moth changes its speed or direction of flight, there is a change in the sound pattern generated by the moth's wing movements.

D. Moth species that can hear the sounds emitted by insect-eating bats are less-likely to be caught by such bats than are moths species that cannot hear these sounds.

E. Moths that are capable of hearing the sounds emitted by insect-eating bats differ in their abilities to use evasive action to escape capture by such bats.
First take: 640 (50M, 27V) - RC needs 300% improvement
Second take: coming soon..
Regards,
HSPA.

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by rohu27 » Sun Apr 17, 2011 6:04 am
is it D?
as it gives an edge to moths which can hear bat's sound.
was confused between D vs E but E just says they use evasive action, but no proof tht action will be successful -wht if they are still cuaght by the bats?
so going for D.

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by aspirant2011 » Sun Apr 17, 2011 9:43 am
Bats emit sounds and generally use the echoes of these sounds highly efficently to detect, locate and catch their preys. However, it is claimed that the characteristic efficiency of this process is reduced by moths able to hear the sounds emitted by insect-eating bats.
Which of the following statements if true, best supports the claim above?

A. Those moths cannot hear the sounds emitted by insect-eating bats live longer on the average than those that can hear such sounds when both kinds of moth are in an environment continuously free of such bats. ---------> goes opposite to the claim

B. Those moths that cannot hear the sounds emitted by insect-eating bats are among the species of insects that are most liekly to be caught by such bats.-------> we dont need to talk about other species

C. When a moth changes its speed or direction of flight, there is a change in the sound pattern generated by the moth's wing movements. ---------> we are not concerned about the wing movements and direction of flight

D. Moth species that can hear the sounds emitted by insect-eating bats are less-likely to be caught by such bats than are moths species that cannot hear these sounds.

E. Moths that are capable of hearing the sounds emitted by insect-eating bats differ in their abilities to use evasive action to escape capture by such bats.---------> no need to discuss about abilities as it is out of scope

whats the OA??????

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by vidhya16 » Sun Apr 17, 2011 11:01 am
IMO - D

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by HSPA » Sun Apr 17, 2011 5:48 pm
OA is D
First take: 640 (50M, 27V) - RC needs 300% improvement
Second take: coming soon..
Regards,
HSPA.