Answer:
option D is correct
Explanation:
cl has 17 electrons if it has 18 it becomes cl-
Acids are danger so stay away
Answer:
4.06 Hz
Explanation:
For simple harmonic motion, frequency is given by
where k is spring constant and m is the mass of the object.
Substituting 0.2 Kg for mass and 130 N/m for k then

Explanation :
(1) Big bang : (1) The most accepted theory on the origin of the universe.
This theory shows the expanding of the universe from high density and high-temperature states.
(2) Steady state : (3) All is the same and will always stay the same.
Steady state means that the properties of any system remain the same always.
(3) Oscillating universe : (4) Agrees with the big bang theory but insists the universe expanded much quicker.
Oscillating universe theory is the result of big bang theory.
(4) Inflation Choices : (2) it's like an inflating and deflating balloon that never stops.
In cosmology, cosmic inflation or deflation is just the expanding and contraction of the universe.
So, the statements and the choices are related as:
(1)-(1)
(2)- (3)
(3)-(4)
(4)-(2)