Answer: it will take him 4.5 hours to cover same distance
Step-by-step explanation:
Marathon runner covered the whole distance in 4 hours running at a constant speed of 8.1 km per hour.
Speed = distance / time
Distance = speed×time
Therefore, distance covered by the marathon runner in in 4 hours, running at a speed of 8.1 km per hour is
8.1 × 4 = 32.4 kilometers
if he decreased the speed to 7.2 km per hour, the distance remains 32.4 kilometers. Therefore,
At 7.2 km per hour, the time it would take him to cover the same distance would be
Distance/ speed = 32.4/7.2 = 4.5 hours
Answer:
B is correct :D brainliest pls
The identity in question is
cos(a - b) = cos(a) cos(b) + sin(a) sin(b)
so that
cos(a - b) = 12/37 cos(a) + 3/5 sin(b)
Since both a and b lie in the first quadrant, both cos(a) and sin(b) will be positive. Then it follows from the Pythagorean identity,
cos²(x) + sin²(x) = 1,
that
cos(a) = √(1 - sin²(a)) = 4/5
and
sin(b) = √(1 - cos²(b)) = 35/37
So,
cos(a - b) = 12/37 • 4/5 + 3/5 • 35/37 = 153/185
The absolute value equation that can be used to find the minimum and maximum radius accepted is:
A. |r - 1.25| = 0.1.
<h3>What is the absolute value?</h3>
The absolute value function is defined as follows:
It measures the distance of a point x to the origin.
In this problem, the absolute value of the difference between the radius and 1.25 cm must be of 0.1 to find the thresholds, hence the equation is:
A. |r - 1.25| = 0.1.
More can be learned about absolute value equations at brainly.com/question/24514895
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The answer is D.
Hopefully this helps! :)
