Why was the usefulness of Dr Cullen’s cooling process missed?___
A. People lacked imagination.
B. It took too long to develop.
C. There was an element of risk.
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What prompted John Gorrie to make his machine?___
A. the onset of personal ill-health
B. unreliable access to natural ice
C. the possibility of becoming rich
Why were the early fridges phased out?___
A. They kept breaking down.
B. They were costly.
C. They were dangerous.
What was the drawback of the new chemicals used?___
A. Their supply was becoming limited.
B. They caused ecological damage.
C. They only had a short shelf-life.
What did Emily Cum m ins want her invention to be?___
A. easy to make
B. safe to use
C. recyclable
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