Complete Question 
The angular speed of an automobile engine is increased at a constant rate from 1120 rev/min to 2560 rev/min in 13.8 s.
 (a) What is its angular acceleration in revolutions per minute-squared
(b) How many revolutions does the engine make during this 20 s interval?
rev
Answer:
a
  
b
  
Explanation:
From the question we are told that 
    The initial  angular speed is 
     The angular speed after 
  is 
     The time for revolution considered is 
  
  Generally the angular acceleration is mathematically represented as 
          
=>      
  
=>      
Generally the number of revolution made is 
  is mathematically represented as 
            
=>      
=>      
 
        
             
        
        
        
In genetic traits, p and q represent the relative probabilities of the two alleles manifesting. If these two are the only options (ex. a dominant one and a recessive one), then the probabilities of both must sum up to 1. In this case, since we are given that q = 0.4, then p + q = 1, p + 0.4 = 1, and p = 0.6.
        
                    
             
        
        
        
Mass movement is the movement of surface materials caused by gravity. A great example would be a mud slide.
        
                    
             
        
        
        
Answer:
The correct option is A = 1960 N/m²
Explanation:
Given that,
Mass m= 20,000kg
Area A = 100m²
Pressure different between top and bottom
Assume the plane has reached a cruising altitude and is not changing elevation. Then sum the forces in the vertical direction is given as
∑Fy = Wp + FL = 0
where 
Wp = is the weight of the plane, and 
FL is the lift pushing up on the plane.
Let solve for FL since the mass of the plane is given:
Wp + FL = 0
FL = -Wp
FL = -mg
FL = -20,000× -9.81
FL = 196,200N
FL should be positive since it is opposing the weight of the plane.
 Let Equate FL to the pressure differential multiplied by the area of the wings:
FL = (Pb −Pt)⋅A
 where Pb and Pt are the static pressures on bottom and top of the wings, respectively
FL = ∆P • A
∆P = FL/A
∆P = 196,200 / 100
∆P = 1962 N/m²
∆P ≈ 1960 N/m²
The pressure difference between the top and bottom surface of each wing when the airplane is in flight at a constant altitude is approximately 1960 N/m². Option A is correct 
 
        
                    
             
        
        
        
Basically, this problem asks you to convert kilocalories (kcal) to kilojoules (kJ). Both are units of energy. To convert kcal to kJ, the equivalence is: 1 kcal = 4.184 kJ. Through dimensional analysis, the solution is as follows:
750 kcal * 4.184 kJ/1 kcal = 3,138 kJ