Answer:
1. 2.67 s
2. 0.1 m/s²
Explanation:
1. Determination of the time taken for the penguin to fall.
Height (h) of cliff = 35 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =? 
h = ½gt²
35 = ½ × 9.8 × t²
35 = 4.9 × t²
Divide both side by 4.9
t² = 35 / 4.9 
Take the square root of both side 
t = √(35 / 4.9)
t = 2.67 s
Thus, it will take 2.67 s for the penguin to fall onto the head of a napping polar bear.
2. Determination of the acceleration of the penguin. 
Initial velocity (u) = 0 m/s. 
Final velocity (v) = 2 m/s.
Time (t) = 20 s
Acceleration (a) =? 
a = (v – u)/t
a = (2 – 0)/ 20
a = 2 / 20
a = 0.1 m/s²
Thus, the acceleration of the penguin is 0.1 m/s²
 
        
             
        
        
        
Answer:
SO4
Explanation:
I'm not sure if you're asking for more than one answer but S04 is one of them, you can search it up if you don't believe me
ion with the subscript of the atoms in a polyatomic ion. There is only ONE Cu and ONE S04, so get the charge for the Cu based on the S04. The formula is S04 , and there is only ONE S04 2, so Cu's charge here must be +2 for the compound to have an overall charge of zero. = copper (Il) ion S04 = sulfate ion then CuS04 = copper (Il) sulfate
 
        
             
        
        
        
Answer:
   the speed of the center of mass stays the same
Explanation:
In a system with no energy loss, momentum is conserved if the mass remains constant. The system described has no change in mass, and energy loss is considered negligible. Hence the product of the total mass and the velocity of its center will be a constant. The center of mass stays the same speed.
 
        
             
        
        
        
The statement to every reacting there is, there is a opposite and same reacting. 
hope it helps