The answer is B) square miles. This is because a city is very big, and the measure it, miles would be ideal.
Answer:
The average rate of change between these times is 68 miles per hour
Step-by-step explanation:
Here, we are to determine the average rate of change between hour 2 and hour 7
The distance traveled at hour 2 is 140 miles
The distance traveled at hour 7 is 480 miles
So we can say we have two points and we want to know the rate of change between these points
Mathematically, we can represent the rate of change as Δ
Thus, between the two different times, we have;
Δ = (D7-D2)/(T7-T2)
where (T7,D7) = (7,480) and (T2,D2) = (2,140) represents the time and distance at hour 2 and hour 7 respectively
Now inputing the values into the equation, we have;
Δ = (480-140)/(7-2) = 340/5 = 68 miles/hour
Many when you solve it it works out perfectly.
(-12)1 because of how you break it down
X + y = 20 --> eqn 1
The second equation would be the mass balance shown below:
(x)(0.40) + y(0.70) = 20(0.52) --> eqn 2
Rearranging eqn 1,x = 20 - ySubstitute this to eqn 2:
(20 - y)(0.40) + y(0.70) = 20(0.52)Solve for y,y = 8 grams Finally, solve for x.x = 20 - 8 = 12 grams
Therefore, Serena needs 12 grams of the 40% solution and 8 grams of the 70% solution.