Ca(NO3)2(aq) + Na2CO3(aq) → 2NaNO3 + CaCO3⬇. NaNO3 is solution so CaCO3 is the precipitate formed.
        
                    
             
        
        
        
Answer is Global Warming causes destruction of our ecosystem due to increased temperatures, drought, fire, weed and pest infestations, more intense storms, water shortages, melting ice caps and glaciers, air pollution. 
        
             
        
        
        
The answer is C. Hope this helps.
        
             
        
        
        
D) The speed of a wave slows as it travels at different speed in different media.
        
                    
             
        
        
        
Answer:
0.231 m/s 
Explanation:
m = mass attached to the spring = 0.405 kg 
k = spring constant of spring = 26.3 N/m 
x₀ = initial position = 3.31 cm = 0.0331 m 
x = final position = (0.5) x₀ = (0.5) (0.0331) = 0.01655 m 
v₀ = initial speed = 0 m/s 
v = final speed = ?
Using conservation of energy 
Initial kinetic energy + initial spring energy = Final kinetic energy + final spring energy 
(0.5) m v₀² + (0.5) k x₀² = (0.5) m v² + (0.5) k x² 
m v₀² + k x₀² = m v² + k x² 
(0.405) (0)² + (26.3) (0.0331)² = (0.405) v² + (26.3) (0.01655)² 
v = 0.231 m/s