Many scientists have been probing psychological problems.

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Many scientists have been probing psychological problems.

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Corrosion can have many causes.

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At least how many tests were carried out by the scientists referred to in this passage

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--- How many lessons do you have every day?- _______________________

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e on the food supply,a supply that some scientists say may have dwindled as a result of the warm waters of El Nino.Most of the whales have been dead for many days before they are found and studied．This makes it hard to find the reason for death.65 whales have been seen in the San Francisco Bay Area this year compared to 17 last year．The whales could be dying from many diseases,but it may be over-population．About how many more whales have been sighted in the San Francisco Bay this year compared t

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