Let the distance of the first part of the race be x, and that of the second part, 15 - x, then
x/8 + (15 - x)/20 = 1.125
5x + 2(15 - x) = 40 x 1.125
5x + 30 - 2x = 45
3x = 45 - 30 = 15
x = 15/3 = 5
Therefore, the distance of the first part of the race is 5 miles and the time is 5/8 = 0.625 hours or 37.5 minutes
The distance of the second part of the race is 15 - 5 = 10 miles and the time is 1.125 - 0.625 = 0.5 hours or 30 minutes.
The function

describes a parabola with vertex = (5, 3).
The graph of the function is attached.
<span>16.45 is less than 16.454. The reason is because 16.454 is 4 thousandths more than 16.45 assuming that both numbers are exact numbers. Although it is only a small amount it still makes 16.45 less than 16.454.</span>
Answer: After 18.05 minutes, the temperature of steel becomes 100 degrees.
Step-by-step explanation:
Since we have given that
Initial temperature = 2500
At t = 0,
we get that

After 2 minutes, the temperature of the steel is 1500 degrees.
so, it becomes,

So, We need to find the number of minutes when the temperature of steel would be 100 degrees.
So, it becomes,

Hence, after 18.05 minutes, the temperature of steel becomes 100 degrees.