<span>a = (v2 - v1)/t= acceleration formula
a = (70 - 0)/7
a = 10 km/hr/sec
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It's better to use as few units as possible.
10 km/hr = 10 km*1000 m/km/(1 hr*3600 sec/hr) = 25/9 m/sec
a= 25/9 m/sec/se</span>
Answer: The cake would be 100F after about 47 minutes
Explanation:
Initial temperature = 210F
Time at 140F = 30 minutes
At 140F the cake has lost (210-140)F
= 70F
70F is lost on 30minutes
Rate of temperature reduction
= (70/30) F/min
= 7/3F/min
To lose 110F from 210 to 100F
Temp/time = 7/3
110/t = 7/3
Cross multiply
t = 330/7
t = 47.1429minutes ~ 47min
I believe that is a Geiger Counter