Explanation:
Work is the dot product of the force and displacement vectors.
W = F · d
In other words, it is the force times the parallel component of the distance.
W = F d cos θ, where θ is the angle between the force and distance.
 
        
             
        
        
        
Mass = 1.2 kg = 1200 grams.
Volume = mass/density = 1200 cm3.
Hope this helps!
        
             
        
        
        
Frictional force and Applied force has same “magnitude” and “opposite” direction.  
Option: B  
<u>Explanation</u>:  
When a book is moved horizontally by applying “force” on the book, the frictional force is opposed to the book by the table. Here, this “frictional force” is opposing the book has the same force what we applied on the book but this frictional force and the applied force are opposite in direction. Always the “frictional force” is opposite to the “applied force” which stops the object to move. For example, if a force applied leftward to the object the frictional force is acted on the right side of the object.
When two objects are in contact they experience a "frictional force". This "frictional force" acts opposite to the force applied on to move the object.
Formula for "frictional force" is 
 Where,  is coefficient of friction and N is normal force.
 is coefficient of friction and N is normal force.
 
        
             
        
        
        
Answer:
the third one is incorrect
Explanation:
10 x 10³= 10^1 x 10^3 = 10^4
 
        
             
        
        
        
Answer:

Explanation:
14 lb force is required to stretch the spring by 4 inch distance
So we have



stretch in the spring is given as

now we will have



Now we need to find the work to stretch it by x = 10 in = 0.254 m
so we have 


