The speed of the cross country runner is equal to 4 km/min.
<u>Given the following data:</u>
To determine the speed of the cross country runner:
Speed can be defined as the distance covered by an individual per unit time and it can be measured in kilometer per minutes (km/min).
Mathematically, speed is given by the formula;

Substituting the given parameters into the formula, we have;

Speed = 4 km/min.
Read more: brainly.com/question/13102821
Answer: a change in energy state occurs. The answer is dark or opaque - not able to be seen through.
Explanation:
The absorption of light makes an object dark or opaque to the wavelengths or colors of the incoming wave: Wood is opaque to visible light. Some materials are opaque to some wavelengths of light, but transparent to others. Glass and water are opaque to ultraviolet light, but transparent to visible light.