Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that passengers using electronic devices put modern airplanes at risk. Why? Because the planes’ navigation systems use low-power circuitry that’s more susceptible to interference than vacuum-tube circuitry in old planes, as illustrated by a recent incident where a navigation system apparently malfunctioned when a passenger opened a laptop.
Notable Assumptions
The author assumes the navigation system’s behavior during the off-course landing was unusual and occurred because the passenger opened their laptop, and not for some other reason. This means assuming laptops and cassette players carried by passengers produce radiation that’s capable of interfering with a modern navigation system.
A
After the laptop computer was turned off, the plane regained course and its navigation instruments and dials returned to normal.
This strengthens the argument by making it more likely the laptop caused the navigation system’s behavior during the off-course landing.
B
When in use all electronic devices emit electromagnetic radiation, which is known to interfere with circuitry.
This strengthens the argument by confirming that cassette players, laptops, and other devices produce radiation. It rules out the possibility that some electronic devices emit no radiation, which would weaken the argument.
C
No problems with navigational equipment or instrument dials have been reported on flights with no passenger-owned electronic devices on board.
This strengthens the argument by ruling out a powerful counterexample. If similar behavior had occurred on flights with no passenger-owned devices, then the laptop’s responsibility would be less likely.
D
Significant electromagnetic radiation from portable electronic devices can travel up to eight meters, and some passenger seats on modern aircraft are located within four meters of the navigation systems.
This strengthens the argument by confirming that passengers sit close enough for radiation from their devices to reach navigation systems. If all the passengers sat too far away for their radiation to reach those systems, the argument would falter.
E
Planes were first equipped with low-power circuitry at about the same time portable electronic devices became popular.
This is irrelevant. The author concludes there’s a risk presently—it doesn’t matter when passenger-owned devices and low-power circuitry became prevalent, so long as they’re both prevalent right now.
Anna: That plan would fail. Cacao, like cloudberries, was once harvested from wild plants. When chocolate became popular in Europe, the cacao gatherers could not supply enough to meet the increased demand, and farmers began to grow large quantities of it at low cost. Now all cacao used in commercial chocolate production is grown on farms. Likewise, if the demand for cloudberries increases, domesticated berries grown on farms will completely supplant berries gathered in the wild.
Summarize Argument: Phenomenon-Hypothesis
Anna concludes if demand for cloudberries increases, then domesticated berries would completely replace wild berries. As evidence, Anna points to what happened in the past with cacao. Cacao was harvested from wild plants until it became popular in Europe. As a result, cacao gatherers could not meet demand and farms began growing large quantities at low cost. Now all cacao used in commercial chocolate production comes from farms, not wild plants.
Describe Method of Reasoning
Anna concludes a cause-and-effect relationship based on what happened in an analogous case. She does this by showing what happened in the past with cacao, and suggests if demand increases for cloudberries in a similar way to cacao the same effect would occur.
A
giving a reason why a proposed course of action would be beneficial to all those affected by it
Anna does not claim Frankie’s proposed course of action would be beneficial to everyone. She believes that Frankie’s proposal would hurt cloudberry gatherers because increased demand would cause the berries to strictly be grown on domestic farms.
B
reinterpreting evidence presented in support of a proposal as a reason to reject the proposal
Anna does not reinterpret any evidence. In fact, Frankie does not provide any evidence for Anna to reinterpret. Anna is the only one who gave evidence in support of her conclusion.
C
projecting the result of following a proposal in a given situation by comparing that situation with a past situation
The past situation being compared is what happened with cacao. The projected result is Anna’s predicted consequence of increasing the demand for cloudberries, resulting in domesticated berries completely replacing wild berries.
D
proposing a general theory as a way of explaining a specific market situation
Anna does not propose a general theory. She cites specific evidence of a past situation in order to make comparisons.
E
contending that the uses for one product are similar to the uses for another product
Anna does not address the subject of use.