Answer:

Step-by-step explanation:
The rate of change in the temperature T of coffee at time t is written as
(remember derivatives are used to express rates of change, and in our case the rate of change of the temperature T). The difference between the temperature M of the air at time t, and the temperature T of the coffee at time t can be expressed as 
Saying that the rate of change in the temperature T is proportional to the difference between M and T is just a way of saying that the rate of change in the temperature T is equal to the difference between M and T, multiplied by some constant k (whose value we don't know, but still that's what it means).
Therefore we get

Answer:
1.5
Step-by-step explanation:
The mean is the Middle number.
1 standard deviation in both sides of 7.5 makes it between 6 and 9.
<u>What is the </u><u>"common difference"</u><u> in 6 to 7.5 and from 7.5 to 9?</u>

and

So, we would say the standard deviation is 1.5
Answer choice A is right.
Answer:
10
Step-by-step explanation:
diameter is half of radius
Answer:
1350 grains
Step-by-step explanation:
Since he needs 450 grains for 6 people, he would need three times that for three times the amount of people.
Therefore, for
people, he would need
grains.
X-3y=-15
-3y=-x-15
-1(-3y=-x-15)
3y=x+15
3/3y=1/3x+15/3
y=1/3x+5