A cup of coffee is initially at $150^{\circ} \mathrm{F}$, which is $80^{\circ} \mathrm{F}$ above room temperature. The difference between the coffee's temperature and the room's temperature decreases at the hourly rate of $80 \%$. Which of the following formulas gives $T(t)$, the coffee's temperature after $t$ hours have elapsed?
A) $ T(t)=150+70(0.2)^{t}$
B) $T(t)=80+70(0.2)^{t}$
C) $T(t)=150+80(0.2)^{t}$
D) $ T(t)=70+80(0.2)^{t}$

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The Answer of A cup of coffee is initially at $150^{\circ} \mathrm{F}$, which is $80^{\circ} \mathrm{F}$ above room temperature. The difference between the coffee's temperature and the room's temperature decreases at the hourly rate of $80 \%$. Which of the following formulas gives $T(t)$, the coffee's temperature after $t$ hours have elapsed?
A) $ T(t)=150+70(0.2)^{t}$
B) $T(t)=80+70(0.2)^{t}$
C) $T(t)=150+80(0.2)^{t}$
D) $ T(t)=70+80(0.2)^{t}$

A Cup of Coffee Is Initially At 150∘F150^{\circ} \mathrm{F}150∘F , Which Is

A Cup of Coffee Is Initially At $150^{\circ} \mathrm{F}$ , Which Is