Answer:
a cold air mass and a warm air mass merge together
 
        
             
        
        
        
The answer would be D. Because the iron fillings are attracted to the magnet underneath the glass.
 
        
                    
             
        
        
        
A natural force of attraction exerted by the earth upon objects, that pulls objects towards earth's center is called<u> </u><u>G</u><u>ravitational</u><u> </u><u>force</u><u> </u><u>.</u>
 
        
             
        
        
        
Answer:
W ≅ 292.97 J
Explanation:
1)What is the work done by tension before the block goes up the incline? (On the horizontal surface.)
Workdone by the tension before the block goes up the incline on the horizontal surface can be calculated using the expression;
W = (Fcosθ)d
Given that:
Tension of the force = 62 N
angle of incline θ =  34°
distance d =5.7 m.
Then; 
W = 62 × cos(34) × 5.7
W = 353.4 cos(34)
W = 353.4 × 0.8290
W = 292.9686 J
W ≅ 292.97 J
Hence,  the work done by tension before the block goes up the incline = 292.97 J