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Differential equations — Question 79

Original QCE Vault practice · 1 mark

Q79 · Practice questionSimple familiar1 mark

QUESTION 79

A cooling model is

T=20+60e^{-0.2t}

, with

t

in minutes. The time when

T=30

is approximately

(A)

5.49

(B)

8.96

(C)

10.99

(D)

17.92

ABCD

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