The correct option is A.
All waves are divided into two basic classes, which are transverse and longitudinal waves. A transverse wave is a type of wave in which the medium of propagation vibrates at angle 90 degree in relation to the direction of propagation. Radio wave is an example of a transverse wave.
Longitudinal studies primarily help discover the relationship between different variables that lack similar background information.
The final velocity of the pebble as it hits the ground is 21.5 m/s.
We have to use the equation;
v = u + gt
Where;
v = final velocity
u = initial velocity
g = acceleration due to gravity
t = time
Since the pebble was dropped from a height, u =0 m/s, hence,
v = gt
v = 9.8 ms-2 × 2.2 s
v = 21.5 m/s
Learn more about velocity: brainly.com/question/8898885
Atoms like carbon and nitrogen do not form ions because the electronegativity of these atoms are not that high nor very low which means electrons are fairly stable in the atom. While chlorine has very high electronegativity and for sodium very low, atoms tend to receive or release electrons.