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:
-72
Step-by-step explanation:
-32 + (2-6)(10)
PEMDAS
Parenthases first
(-4)(10)
multiply together
(-40)
Then just add the -32 and since a negative plus a negative is always negative the answer is going to be negative
-32 + (-40)
= -72
1. Correct answer is a (since when you are not given the n values, it is implied that the first value is 1).
3. Correct answer is a (a(n)=-3+4(1-1)=-3).
7. The pattern is to reduce the previous value by 4, thus the 12th term of the sequence is -24 (a(n)=20 - 4(n-1)=20 - 4(12-1)=-24).
8. Missing term is 26 (32+20=52; 52/2=26).
10. Pattern is 625/1=625; 625/5=125; 125/5=25; 25/5=5, thus. the 10th term is 1/3125 (answer a).
