Answer:

Explanation:
Initial angular speed of the ferris wheel is given as



final angular speed after friction is given as



now angular acceleration is given as



now torque due to friction on the wheel is given as



Now the power required to rotate it with initial given speed is


 
 
 
        
             
        
        
        
From Carnot's theorem, for any engine working between these two temperatures:
efficiency <= (1-tc/th) * 100
Given: tc = 300k (from question assuming it is not 5300 as it seems)
For a, th = 900k, efficiency = (1-300/900) = 70%
For b, th = 500k, efficiency = (1-300/500) = 40% 
For c, th = 375k, efficiency = (1-300/375) = 20% 
Hence in case of a and b, efficiency claimed is lesser than efficiency calculated, which is valid case and in case of c, however efficiency claimed is greater which is invalid. 
 
        
             
        
        
        
The time for the car to drive directly south is determined as 7.15 s.
<h3>Time for the car to drive directly west</h3>
The time for the car to drive directly south is determined by applying the concept of slope.
slope = Δy/Δx
a = Δv/Δt
Δt = Δv/a
Δt = (26.8)/(3.75)
Δt = 7.15 s
Thus, the time for the car to drive directly south is determined as 7.15 s.
Learn more about acceleration here: brainly.com/question/605631
#SPJ1
 
        
                    
             
        
        
        
Answer:
Explanation:
Let r be the rate of the slower walker in mph
[r + (r + 1.7)](2) = 13
     (2r + 1.7)(2) = 13
          4r + 3.4 = 13
                   4r = 9.6
                     r = 2.4 mph
             r + 1.7 = 4.1 mph          
 
        
             
        
        
        
I believe it is respiration