Answer: His average speed in mph over the last 400 m is 7.7 m/s.
Explanation:
Given: Hicham El Guerrouj of Morocco holds the world record in the 1500 m running race. He ran the final 400 m in a time of 51.9 s.
We know that , speed = 
Here , distance = 400m and time = 51.9 s
Then, speed = 
Hence, his average speed in mph over the last 400 m is 7.7 m/s.
Answer: the air above a wildfire
Explanation:
First part of question is: The diagram shows currents that form as water is heated.
When water is being heated from below, convection currents are used. This happens when the molecules at the bottom are heated thus giving them energy and enabling them rise to the surface. The colder water at the surface will therefore sink to the bottom where is is heated making it rise as well and the process is repeated.
When a wildfire is ignited, the concept is the same. The air above the wildfire is the water in this scenario. It is heated at the bottom and rises thereby forcing the air above to come down and be heated as well. Both situations uses convectional currents.
Answer:
Static stretching.
Explanation:
It is static stretching because it is a form of stretching which u can do actively for a period of time and you hold position for about 30 to 60 seconds which allow the muscles and connective tissues to lengthen. It is done after work out with out movement in order to loosen up muscles so as to gain flexibility.
