It is b because it has one of the most simple method.
Quick answer: 68oF <<<<
A quick way to figure this out is to double the C temperature and add 30, just so you get an estimate.
F ~ 2*20 + 30 ~ 70oF
Now let's use the actual formula
F = 9/5 * C + 32
F = 9/5 * 20 + 32
F = 180/5 + 32
F = 36 + 32
F = 68o
68oC <<<<< answer.
Step-by-step explanation:
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