Answer:
Electron groups could be considered as  Lone pair electrons and bonded pairs of electrons.
Answer: Option D & B
Explanation:
The two or more electrons can be bonded by single bond, double bond, covalent bond of electrons can simply be lone pair of electrons. Unshared pair of electrons are generally termed as lone pair of electrons in an atom which are generally present in the outermost shell of atoms. Hence electron groups can be determined by bonded pairs and lone pairs of electrons.
I got this from another brainly user
 
        
             
        
        
        
Answer:
3.49 seconds
3.75 seconds
-43200 ft/s²
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration

Time the parachutist falls without friction is 3.19 seconds

Speed of the parachutist when he opens the parachute 31.32 m/s. Now, this will be considered as the initial velocity

So, time the parachutist stayed in the air was 3.19+0.3 = 3.49 seconds


Now the initial velocity of the last half height will be the final velocity of the first half height.

Since the height are equal


Time taken to fall the first half is 2.65 seconds
Total time taken to fall is 2.65+1.1 = 3.75 seconds.
When an object is thrown with a velocity upwards then the velocity of the object at the point to where it was thrown becomes equal to the initial velocity.

Magnitude of acceleration is -43200 ft/s²
 
        
             
        
        
        
Answer:
This difference is kept to a minimum because the resistance in transformers is a few tens of ohms and the resistance of modern voltmeters is of the order of MΩ.
Explanation:
A voltmeter is built by a galvanometer and a resistance in series, this set is connected in parallel to the resistance where the voltage is to be measured, therefore the voltage is divided between the voltmeter and the element to be measured, consequently the measured voltage It is less than the calculated one, since for them the resistance of the voltmeter is assumed infinite.
This difference is kept to a minimum because the resistance in transformers is a few tens of ohms and the resistance of modern voltmeters is of the order of MΩ.
 
        
             
        
        
        
Infrared, visible light, then ultraviolet. Infrared is light that the human eye can not see and visible light is clearly light we can see then ultraviolet is has such a high frequency we can't see it either.
        
                    
             
        
        
        
Answer:
0.25m/s
Explanation:
Given parameters
m₁  = 5kg 
v₁ = 1.0m/s 
m₂ = 15kg 
v₂ = 0m/s 
Unknown: 
velocity after collision = ? 
Solution: 
Momentum before collision and after collision will be the same. For inelastic collision; 
     m₁v₁ + m₂v₂  = v(m₁ + m₂)
Insert parameters and solve for v; 
    5 x 1  + 15 x 0 = v (5 + 15 )
           5  = 20v 
           v =  = 0.25m/s
   = 0.25m/s