- You will hear a news item once. It is about 1.5 minutes long.
- Then 5 questions will appear.
- Choose the best way to complete each statement from the drop-down menu.
AI explanationShows the answer. Tap to open.
Correct Answer: our solar system.
Why this is correct: The report defines exoplanets as planets outside our solar system. It does not say only three exoplanets exist.
Why the other options are wrong:
- Earth's atmosphere.: Earth's atmosphere is not the defining boundary used in the report.
- the Milky Way.: The study concerns planets in the Milky Way; exoplanets need not be outside the galaxy.
- the Moon's orbit.: The Moon's orbit is not the boundary used to define an exoplanet.
Correct Answer: one planet
Why this is correct: The survey gives an average minimum of one planet per star in the galaxy. This statistical average is not a guarantee about each individual star.
Why the other options are wrong:
- one moon: The result counts planets, not moons.
- one star: One star per star does not express the reported planet-to-star ratio.
- two planets: The reported minimum is one planet on average, not two.
Correct Answer: microlensing.
Why this is correct: The study uses the technique called microlensing to survey the galaxy for planets. The report then explains how one star magnifies light from another to reveal planets.
Why the other options are wrong:
- the Planet Probing Lensing Anomalies Network.: The named Network is the observing collaboration, not the survey technique.
- a huge telescope.: A huge telescope is not the technique named in this report. The stated method is microlensing.
- a physical glass lens.: The report compares a star to a magnifying lens; it does not identify a physical glass lens as the technique.
Correct Answer: more numerous than large planets.
Why this is correct: The report says there are more small planets than large ones in the galaxy. The answer must preserve the direction of this comparison.
Why the other options are wrong:
- as numerous as large planets.: The study does not say the numbers are equal; it reports more small planets.
- less numerous than large planets.: Fewer small planets reverses the stated comparison.
- too faint for the survey to compare.: The survey gives a small-versus-large comparison, so it does not say the planets are too faint to compare.
Correct Answer: a magnifying lens
Why this is correct: The report explains that one star acts like a magnifying lens to brighten light from a background star.
Why the other options are wrong:
- a barrier that blocks light: Blocking light is opposite to the described brightening effect.
- a device that absorbs starlight: The described light is brightened rather than absorbed.
- a screen that darkens the image: Darkening the image reverses the stated brightening effect.
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