first one is true, there's no net force acting on it thats greater than another or making it unbalanced, if there was the object would be in some kind of motion
All scientist use meters, that way scientist can share information across country without needing to convert the data.
3. is air resistance
4. The large rock
 
        
             
        
        
        
Sifting is the best method cuz all the dirt will be carried by wind.
 
        
                    
             
        
        
        
Newton's second law tells you: 
Sum of forces on an object = ma 
Here, the forces acting on the bundle are the tension in the string and the force of gravity, these two must combine to yield the acceleration of the bundle. 
So we have: 
T-mg = ma 
or T=m(g+a) 
We know m=8.7kg, we need to find a from the information 
starting from rest, an accelerating object covers distance according to: 
<span>dist = 1/2 at^2 </span>
to cover 1m in 1.8s, we have: 
a=2d/t^2 = 2x1/1.8^2 = 0.62 m/s/s 
Thus, the tension in the string is: 
<span>T = m(g+a)
=  8.7</span>kg(9.8m/s/s+0.62m/s/s) 
<span>
<span>T =  90.654 N
</span>
I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
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