Answer:
yuki.ki
Step-by-step explanation:
Assume the old of Jack is X and the old of Lacy is Y
so ...
do the mathematical model ...
.
X=2Y
(X+7)+(Y+7)= 35
-
THEN
Solve the equation
y= 7
x = 14
Answer: the answer is the second option.
Step-by-step explanation:
T = 12 min, T o = 80° C, T s = 50 °C, T ( 12 ) = 60° C
60 = 50 + ( 80 - 50 ) · e^(-12k)
10 = 30 · e^(-12k)
e^(-12k) = 0.3333...
ln ( 0.333.. ) = - 12 k
- 12 k = - 1.1
k = ( - 1.1 ) : ( - 12 ) = 0.0916
Answer: D ) 0.0916
