Read the following passage.
A. The first satellite tag on a wild animal dates from 1970. That year, researchers in Wyoming put a satellite collar on an elk named Monique. The collar weighed 10 kg and sent an analogue VHF signal. Over the following decades, tags of this kind led to new findings on whale journeys and on the migrations of herd animals. However, these early tags were heavy and had low accuracy. Nearly four decades after Monique, they were still too heavy for 75 per cent of birds and mammals.
B. Much of this work has relied on the Argos system. Each tag carries a transmitter that sends short messages lasting less than one second. Satellites flying 650 to 850 km above the Earth in polar orbits pick up these messages, and each one takes about 100 minutes to circle the planet. A satellite can hear every transmitter inside a circle about 5,000 km wide, and a pass over any one tag lasts about 10 minutes on average. The tag's position is calculated from Doppler effect measurements of its signal. If no ground station is in contact, the satellite stores the message until it flies over one.
C. A newer system called Icarus first operated in 2020 as an experiment on the International Space Station, where an antenna collected signals from lightweight sensors attached to animals. In 2022, the war in Ukraine brought the project's collaboration with Russia to an end, and Icarus stopped work. Engineers then miniaturized the receiver into a payload about ten centimetres long that can fly on a tiny satellite called a CubeSat. Compared with the station prototype, it uses one tenth of the energy and reads four times as many sensors. After a pause of about three years, the first new receiver went into orbit on 28 November, and six receivers are expected by the middle of 2027.
D. Scientists still disagree about how much the tags themselves affect animals. In a pool at the Vancouver Aquarium, researchers from the University of British Columbia found that trained northern fur seals swam three to six per cent slower and used 12 to 19 per cent more energy when wearing a tag. NOAA scientists who tagged wild fur seals in the Bering Sea point to studies suggesting that the animals adapt over time. The pool trials were short, however, and long-term effects were not measured. Writing in Hakai Magazine in 2018, both sides agreed that more work was needed to find out whether wild fur seals pay a price for wearing tags.
E. Not given in any of the above paragraphs.
Decide which paragraph, A to D, has the information given in each statement below. Select E if the information is not given in any of the paragraphs.
AI explanationShows the answer. Tap to open.
Correct Answer: B
Why this is correct: Look at Paragraph B. A satellite hears every transmitter inside a circle about 5,000 km wide. But a pass over any one tag lasts about 10 minutes on average. Ten minutes is a short period.
Passage Reference: A satellite can hear every transmitter inside a circle about 5,000 km wide, and a pass over any one tag lasts about 10 minutes on average.
Tips: Focus on one trip overhead. Find how long a satellite can pick up a single device, and decide if that is short.
Why the other options are wrong:
- A: Paragraph A describes the first collar and its analogue signal. There is no time given for hearing a tag.
- C: Paragraph C covers the Icarus receivers and how many sensors they read. Time spent over one tag is not given.
- D: Paragraph D is about how tags affect fur seals. Satellite passes are not part of it.
- E: The ten-minute pass is in Paragraph B, in the sentence about the 5,000 km circle.
Correct Answer: E
Passage Reference: If no ground station is in contact, the satellite stores the message until it flies over one.
Why this is correct: Look at Paragraph B. The satellite stores a message until it flies over a ground station. It never says how long that can take. A full day is a detail the text leaves out.
Tips: Paragraph B tells you messages are stored. Check whether it also says for how long.
Why the other options are wrong:
- A: Paragraph A explains that early tags were heavy and not accurate. Storing messages in space is not mentioned.
- B: Storage on board is in Paragraph B, but with no time limit. The idea of a full day is not there.
- C: Paragraph C gives dates for Icarus, like 2020 and 2022. Waiting times for messages are not given.
- D: Paragraph D reports pool trials with fur seals. It has nothing about satellites keeping data.
Correct Answer: A
Passage Reference: That year, researchers in Wyoming put a satellite collar on an elk named Monique.
Why this is correct: Look at Paragraph A. In 1970, researchers in Wyoming put a satellite collar on an elk named Monique. The next sentence says the collar weighed 10 kg. So one named animal wore the first satellite tag, and it was heavy.
Tips: Look for an animal with a name. Only one paragraph gives one.
Why the other options are wrong:
- B: Paragraph B explains how Argos satellites hear tags. It gives no weight and names no animal.
- C: Paragraph C talks about lightweight sensors on Icarus. That is the newer system, not the first collar.
- D: Paragraph D names fur seals in a pool, but none of them has a name. It does not describe the first collar.
- E: Monique and the 10 kg collar both appear near the start of Paragraph A.
Correct Answer: E
Passage Reference: After a pause of about three years, the first new receiver went into orbit on 28 November, and six receivers are expected by the middle of 2027.
Why this is correct: In Paragraph C, the first new receiver went into orbit on 28 November. It does not say who paid for the rocket. No company is named in the paragraph.
Tips: Paragraph C says when the receiver went up. Ask if it also says who paid.
Why the other options are wrong:
- A: Paragraph A is about the first collar on an elk in Wyoming. Nothing is launched into space there.
- B: Paragraph B describes satellites in polar orbits. It never says who launched or paid for them.
- C: The launch on 28 November is in Paragraph C. Who paid for it is missing.
- D: Paragraph D names the Vancouver Aquarium and NOAA. They study seals and do not pay for rockets.
Correct Answer: D
Passage Reference: In a pool at the Vancouver Aquarium, researchers from the University of British Columbia found that trained northern fur seals swam three to six per cent slower and used 12 to 19 per cent more energy when wearing a tag.
Why this is correct: Paragraph D describes the pool at the Vancouver Aquarium. Trained fur seals swam three to six per cent slower with a tag. They also used 12 to 19 per cent more energy.
Tips: Paragraph C also talks about energy. Check whose energy is being measured.
Why the other options are wrong:
- A: Paragraph A says early tags were heavy. It does not measure how any animal moved with one.
- B: Paragraph B covers tags sending short messages. It does not test animals in water.
- C: Paragraph C says the new receiver uses less energy. That is the machine's energy, not an animal's.
- E: The pool trials with fur seals are described in Paragraph D.
Correct Answer: C
Passage Reference: In 2022, the war in Ukraine brought the project's collaboration with Russia to an end, and Icarus stopped work.
Why this is correct: Look at Paragraph C. Icarus first worked on the International Space Station in 2020. In 2022, the war in Ukraine brought the project's collaboration with Russia to an end.
Tips: Find where Ukraine comes up. Then check what ended and who the partner was.
Why the other options are wrong:
- A: Paragraph A is set in Wyoming in 1970. It has no war and no partner country.
- B: Paragraph B describes the Argos system. Russia and Ukraine are not mentioned.
- D: Paragraph D mentions disagreement between scientists about tags. That is not the same as a partnership ending.
- E: Paragraph C gives this in its second sentence, with the year 2022.
Correct Answer: E
Passage Reference: In a pool at the Vancouver Aquarium, researchers from the University of British Columbia found that trained northern fur seals swam three to six per cent slower and used 12 to 19 per cent more energy when wearing a tag.
Why this is correct: Look at Paragraph D. The pool tests used trained northern fur seals at the Vancouver Aquarium. The paragraph never says why trained animals were used. Cost is not mentioned.
Tips: The paragraph tells you where the tests happened. Check whether it also says why.
Why the other options are wrong:
- A: Paragraph A is about early heavy tags and the elk named Monique. Seals do not appear.
- B: Paragraph B explains how Argos satellites pick up signals. It has no pool tests.
- C: Paragraph C describes the Icarus receivers in space. Seals are not part of it.
- D: Paragraph D describes the pool tests and what they found. It does not say why they were done there.
Correct Answer: C
Passage Reference: Compared with the station prototype, it uses one tenth of the energy and reads four times as many sensors.
Why this is correct: Paragraph C compares the new receiver with the station prototype. It uses one tenth of the energy. One tenth is a small fraction.
Tips: Paragraph D also has energy numbers. Make sure you pick the one about the receiver.
Why the other options are wrong:
- A: Paragraph A says early tags were heavy. It does not compare the power needs of two receivers.
- B: Paragraph B describes Argos transmitters sending short messages. Power use is not given.
- D: Paragraph D reports more energy used by seals with tags. That is about animals, not a receiver.
- E: The one tenth figure for the new receiver is in Paragraph C.
Correct Answer: A
Passage Reference: Nearly four decades after Monique, they were still too heavy for 75 per cent of birds and mammals.
Why this is correct: Paragraph A ends with this idea. Nearly four decades after Monique, tags were still too heavy for 75 per cent of birds and mammals. That is most of them.
Tips: Focus on birds and mammals decades after the first device. How many of them could not carry one?
Why the other options are wrong:
- B: Paragraph B explains how satellites receive messages. The size of animals is not discussed.
- C: Paragraph C mentions lightweight sensors on animals. It does not say how many animals could carry older tags.
- D: Paragraph D shows a tag slowing fur seals. It does not say most animals were too small for tags.
- E: The 75 per cent figure closes Paragraph A.
The rest of this explanation is for members. Sign in free to read why the other options are wrong, key words and tips.
Sign in to read the full explanation