Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
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Question: An Australian inventor has designed and built an environmentally friendly ferry that uses solar and wind power to transport people around Sydney Harbor. Robert Dane and his Solar Sailor were given the top prize at the Australian Design Awards recently. The Solar Sailor has been in use for six months. It uses four sources of energy for its power -- solar, wind, battery power with stored solar energy and a fuel generator in store all controlled by computers. The ferry can travel up to 7.5 knots on just wind and solar power. It's solar wings and fiberglass solar panels which not only take in sunlight and store it in batteries, but also act as sails. "We angle our solar panels to the sun in two planes , which increases the amount of energy we get from the sun by 40 percent," Dane says. "And also we can use that same structure to do another job, which is also the sail, and so these wing sails actually push the ferry forward just like a soft sail does." Computers check the sun and wind and angle the solar wings to take in the most sunlight. If there isn't much wind or it is a cloudy day, energy stored in the batteries runs the electric motor for up to five hours. "If the batteries are too low, then the computer turns the generator on so the boat is always able to meet a commercial schedule, or get from point A to point B no matter what," Dan explains. Dane got his idea for the Solar Sailor from a book on insects. He was amazed how insects use their wings to collect solar energy to warm themselves. "When I read that, I realized there was a good example in nature for what we were going to do, which was to use a solar wing to collect solar energy and also to sail," he says.

Answer: What is the Solar Sailor?

Question: The purpose of this paper is to assess the reliability and validity of the Spanish version of the Davidson trauma scale (DTS-S) and to determine the prevalence and correlates of post-traumatic stress disorder (PTSD) symptoms in a non-clinical random sample of prison inmates. Probabilistic samples of 1,179 inmates from 26 penal institutions in Puerto Rico were selected using a multistage sampling design. Population estimates and correlations were obtained for PTSD, generalized anxiety and depression. The reliability, factor structure, and convergent validity of the DTS-S were assessed. Cross-validation was employed to confirm the results of the factor analyses. Using the cut-offs adopted by the scale's author, 136 (13.4 percent) of the inmates are likely to have current PTSD and 117 (11.6 percent) reach the cut-off for sub-threshold PTSD. Confirmatory factor analysis generated two factors explaining 53 percent of the variance. High reliabilities were obtained for the total scale (=0.95) and for the frequency and severity scales (=0.90 and 0.91). Significantly higher DTS-S scores were found for females (t=2.26, p<0.025), for inmates diagnosed with depression or anxiety (t=2.02, p<0.05), and those reporting suicide attempts (t=4.47, p<0.0001). Findings support that the DTS-S is a reliable and valid measure to assess PTSD symptoms in Latino inmate populations and to identify individuals at risk for the disorder that require confirmatory diagnosis and clinical interventions.

Answer: Symptoms of which disorder are evaluated with the Davidson Trauma Scale?

Question: According to 2011 census of India, Kumbakonam had a population of 140,156 with a sex-ratio of 1,021 females for every 1,000 males, much above the national average of 929. A total of 12,791 were under the age of six, constituting 6,495 males and 6,296 females.The average literacy of the city was 83.21%, compared to the national average of 72.99%. There were a total of 9,519 workers, comprising 32 cultivators, 83 main agricultural labourers, 1,206 in house hold industries, 7,169 other workers, 1,029 marginal workers, 24 marginal cultivators, 45 marginal agricultural labourers, 212 marginal workers in household industries and 0 other marginal workers.

Answer:
According to the census, which group is smaller: house hold industries or cultivators?