Mechanical advantage is the amount by which a machine multiplies input force. It is a measure of the force amplification using a tool or machine system. 
        
             
        
        
        
Answer:
Explanation:
The trick is in finding the volume.
Final Volume = 26.64
Initial Volume=<u>20.92</u>                   Subtract
Metal Volume  5.72  cm^3
Density = mass / volume
Density = 72.17 / 5.72
Density = 12.617
 
        
             
        
        
        
At the highest point in its trajectory, the ball's acceleration is zero but its velocity is not zero. 
<h3>What's the velocity of the ball at the highest point of the trajectory?</h3>
- At the highest point, the ball doesn't go more high. So its vertical velocity is zero.
- However, the ball moves horizontal, so its horizontal component of velocity is non - zero i.e. u×cosθ. 
- u= initial velocity, θ= angle of projection
<h3>What's the acceleration of the ball at the highest point of projectile?</h3>
- During the whole projectile motion, the earth exerts the gravitational force with a acceleration of gravity along vertical direction. 
- But as there's no acceleration along vertical direction, so the acceleration along vertical direction is zero.
Thus, we can conclude that the acceleration is zero and velocity is non-zero at the highest point projectile motion.
Disclaimer: The question was given incomplete on the portal. Here is the complete question.
Question: Player kicks a soccer ball in a high arc toward the opponent's goal. At the highest point in its trajectory
A- neither the ball's velocity nor its acceleration are zero. 
B- the ball's acceleration points upward. 
C- the ball's acceleration is zero but its velocity is not zero. 
D- the ball's velocity points downward.
Learn more about the projectile motion here:
brainly.com/question/24216590
#SPJ1
 
        
             
        
        
        
Answer:
1 kg lead to earth is greater attraction as mass of earth is much more than 1kg lead.
Explanation:
Objects with more mass have more gravity. Gravity also gets weaker with distance. So, the closer objects are to each other, the stronger their gravitational pull is. Earth's gravity comes from all its mass
 
        
             
        
        
        
Density =mass/volume
density= (0.044kg/(11 x10^-6)
4000kg/m^3