Buffers neutralize the acid and the bases
        
             
        
        
        
Upthrust is the upward force exerted by fluids on the surface of an object immersed in fluids. Thrust:- It is the force acting perpendicular to the surface. Upthrust:- It is the upward force exerted by the fluid on the surface of an object immersed in liquid.
I hope it's help you
 
        
             
        
        
        
Average speed = (total distance covered) / (time to cover the distance)
Total distance = (77km + 66km) = 143 kilometers
Time to cover the distance = 2 hours
Average speed = (143 km) / (2 hours) =  71.5 km per hour
        
             
        
        
        
The If a car is going round a curve , there is an acceleration because the direction of the velocity changes.
<h3>What is the direction of the velocity?</h3>
Now we know that if you throw the ball upwards, the motion is in opposite direction to gravity thus the ball is experiencing deceleration and the speed decreases. The velocity decreases and the acceleration is negative.
If the ball is coming down, then the ball is accelerated thus it speeds up and the direction of the acceleration is positive.
If a car is going round a curve, the vehicle is accelerating because the direction of the velocity changes even if its amount remains constant.
When a board is moving down a hill at 2 ms-1, it is experiencing an acceleration because the motion is in the same direction as gravity.
If a car is coming to a stop at a point, it experiences a deceleration and not an acceleration since the change of velocity with time is negative as the car comes to rest.
Learn more about acceleration:brainly.com/question/12550364
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