Answer:
NaNO3.
Explanation:
The Na ion has one positive charge and the NO3 ion has one negative charge so the correct formula is NaNO3.
 
        
             
        
        
        
Answer:
The energy lost by the atoms is given off as an electromagnetic wave. ... even if it's not very intense, will always cause electrons to be emitted.
Explanation:
 
        
             
        
        
        
Answer:
2.When they reach the bottom of the fall
Explanation:
The potential energy of the waterfall is maximum at the maximum height and decreases with decrease in height. Based on the law of conservation of mechanical energy, as the potential energy of the water fall is decreasing with  decrease in height of the fall, its kinetic energy will be increasing and the kinetic energy will be maximum at zero height (bottom of the fall).
Thus, the correct option is "2" When they reach the bottom of the fall
 
        
             
        
        
        
Answer:
36.87 km/h
Explanation:
Convert all the units in SI system 
1 mile = 1609.34 m
d1 = 6 mi = 9656.04 m
t1 = 15 min = 15 x 60 = 900 s
d2 = 3 mi = 4828.02 m
t2 = 10 min = 10 x 60 = 600 s
d3 = 1 mi = 1609.34 m 
t3 = 2 min = 2 x 60 = 120 s 
d4 = 0.5 mi = 804.67 m
t4 = 0.5 min = 0.5 x 60 = 30 s
Total distance, d = d1 + d2 + d3 + d4 
d = 9656.04 + 4828.02 +  1609.34 + 804.67 = 16898.07 m = 16.898 km
total time, t = t1 + t2 + t3 + t4 
t = 900 + 600 + 120 + 30 = 1650 s = 0.4583 h 
The ratio of the total distance covered to the total time taken is called average speed. 
Average speed = 16.898 / 0.4583 = 36.87 km/h
 
        
             
        
        
        
Answer:
 a = 1 m/s²  and 
Explanation:
The first two parts can be seen in attachment
We use Newton's second law on each axis
Y axis
       Ty - W = 0         
       Ty = w
X axis
      Tx = m a
With trigonometry we find the components of tension
     Sin θ = Ty / T
     Ty = T sin θ
     Cos θ = Tx / T
     Tx = T cos θ
We calculate the acceleration with kinematics
    Vf = Vo + a t
    a = (Vf -Vo) / t
    a = (20 -10) / 10
    a = 1 m/s²
We substitute in Newton's equations
      
   T Sin θ = mg
   T cos θ = ma
We divide the two equations
   Tan θ = g / a
   θ = tan⁻¹ (g / a)
   θ = tan⁻¹ (9.8 / 1)
   θ = 84º
We see that in the expression of the angle the mass does not appear therefore you should not change the angle