A student writes: "Coral cover in Batangas Bay is falling, because Dr. Reyes, a marine biologist, says so." Which form of evidence does this support use?

Liza writes: "My grandmother rode the 6 a.m. ferry last Tuesday, and it left forty minutes late." Which form of evidence is her support?

A team recorded the water temperature at the same reef site every morning for two years and averaged the readings. Which form of evidence do their findings rest on?

Which proposition can properly rest on self-evidence alone, with no study, story or expert behind it?

An essay begins: "It goes without saying that phones ruin every student's grades." Why does this fail as self-evidence?

A public health physician is asked whether a new dengue vaccine caused fever during trials. She answers from the trial results. Is this appeal to authority legitimate?

A well-known movie actor tells viewers that a vitamin brand prevents colds. He has no medical training. Which weakness does this appeal to authority have?

A journal article reports that a soft drink harms no one. The author is paid by the drink's maker, and the article never says so. Which weakness does this appeal to authority have?

A famous composer is asked whether the melody of a hymn is beautiful. She answers that it is. Why is her answer not a strong argument from authority?

Ramon says the school gate was locked at 7:05 on Monday. He was standing at the gate and found it locked. Is his single report good evidence for that claim?

Mila argues that smoking harms no one, because her uncle smoked for fifty years and stayed healthy. Why is her support weak?

A newspaper reports: "The bridge is safe, according to the chief engineer who inspected it." Which form of evidence does the newspaper offer readers?

An economist who studies rice prices predicts the exact price of rice in the year 2035. A writer cites this as proof. Why is the appeal weak?

For a report, Ana cites the national weather bureau's rainfall totals for Cebu last year. Is this appeal to authority legitimate?

A writer states: "A part is smaller than the whole it belongs to." He offers no study, no story and no expert. Which form of evidence is he relying on?

Which statement about arguments from authority is correct?

Two people are asked why a reef is bleaching: a marine biologist who studies reefs, and a chef who has dived at many reefs. Whose statement is a legitimate argument from authority?

A health worker wrote up one family's account of when mosquitoes bit them at home. Which form of evidence is this write-up?

A student claims water boils at a lower temperature high on a mountain, and supports it with thermometer readings taken at three altitudes. Which form of evidence is the support?

A cigarette maker's own laboratory reports that its new cigarette is safer. No independent laboratory has tested it. Which weakness does this appeal to authority have?