N is 12
because if you add 4 and 3 you get 7.
84 divided by 7 is 12.
Answer:
9.4 secs
Step-by-step explanation:
From Newton's law of cooling;
T(t) = Ts + Do e^-kt
Where;
D0= initial temperature difference
Ts= Temperature of the surroundings
t= time
K = positive constant
Do = 185 - 60 = 125 degrees
167 = 60 + 125 e^-3k
167 - 60 = 125 e^-3k
107/125 = e^-3k
ln(e^-3k) = ln(107/125)
-3k = -0.1555
k = 0.1555/3
k = 0.0518
Substituting the value of k to find the time taken to reach 137 degrees
T(t) = Ts + Do e^-kt
137 = 60 + 125 e^-(0.0518t)
137 - 60 = 125 e^-(0.0518t)
77 = 125 e^-(0.0518t)
e^-(0.0518t)= 77/125
ln [e^-(0.0518t)] = ln(77/125)
-0.0518t = -0.4845
t = 0.4845/0.0518
t = 9.4 secs
Answer:
sorry the question is not clear enough
Question 13: The answer is D
Question 7: The answer is C
Question 14: The answer is B
And the question for the last Pic, the correct graph is B.
