Answer:
6.26 m/s 
Explanation:
Pretty slow.... the PE (Potential Energy) at 2m will be converted to KE (Kinetic Energy) at the bottom of the track (neglecting friction)
PE    =   KE 
mgh = 1/2 mv^2     divide both sides of the equation by 'm'
gh    = 1/2 v^2             multiply both sides by 2 
2 gh = v^2               take sqrt of both sides
v = sqrt ( 2gh) = sqrt ( 2*9.81*2) = 6.26 m/s 
 
        
             
        
        
        
Explanation:
Speed of the marathon runner, v = 9.51 mi/hr
Distance covered by the runner, d = 26.220 mile
Let t is the time taken by the marathon runner. We know that the speed of the runner is given by total distance divided by total time taken. Mathematically, it is given by :



t = 2.75 hours
Since, 1 hour = 60 minutes
t = 165 minutes
Since, 1 minute = 60 seconds
t = 9900 seconds
Hence, this is the required solution.
 
        
             
        
        
        
The answer is C because <span>this movement is caused by the heat in Earth and creates </span>convection currents. <span>Convection currents in the asthenosphere cause movement of Earth's tectonic plates. </span> 
        
                    
             
        
        
        
Answer: yes a quantity have different dimensions in different system of units . No,because in different system of units doesn't change the quantity but it only changes the numerical.
Good luck !
        
                    
             
        
        
        
I believe it is -1.11 m/s^2. I will let you know if its correct