This question is the application of differential eqns in order to derive a model for the temperature dependence with time. Actually, a general equation has already been derived for this type of cases. This equation is known as the Newton's Law of Cooling. The equation is
(T - Ts) / (To -Ts) = e^(-kt)
where T is the the temperature at any time t
Ts is the surrounding temperature
To is the initial temperature
k is the constant
t is the time
several assumptions have been made to arrive at this form, i suggest you trace the derivation of the general formula.
First we need to look for k using the initial conditions that is @t = 1.5 min, T = 50 F
substituting we get a k = 0.2703
therefore @ t = 1 min, T = 55.79 F
@ T = 15 F the time required is 9.193 min.
He would most likely be referring to kilometers if it is a large area. So D would be your answer.
What does x equal to
Step-by-step explanation:
Answer:
8X+.07Y=W
Step-by-step explanation:
x is your hours and y is your sales
he makes 8 an hour, hence 8X or 8 x X
7 percent written as a decimal is .07 and his commission for sales, so .07Y
add them together and you get your equation:
8X+.07Y=W
