Answer:
D. 4000 km
Explanation:
f = Frequency of wave that is being transmitted = 76 Hz
= Wavelength of wave that is being transmitted
v = The velocity of electromagnetic waves through air = 
Velocity of a wave is given by

Hence, the approximate wavelength of the waves is 4000 km
Answer:
<em>The distance is now 4d</em>
Explanation:
<u>Mechanical Force</u>
According to the second Newton's law, the net force exerted by an external agent on an object of mass m is:
F = m.a
Where a is the acceleration of the object.
The acceleration can be calculated by solving for a:

Once we know the acceleration, we can calculate the distance traveled by the block as follows:

If the block starts from rest, vo=0:

Substituting the value of the acceleration:

Simplifying:

When a force F'=4F is applied and assuming the mass is the same, the new acceleration is:

And the distance is now:

Dividing d'/d:

Simplifying:

Thus:
d' = 4d
The distance is now 4d
It would be 20 protons left because 1-19= 20
Answer:
When thermal energy is added to a substance, its temperature increases, which can change its state from solid to liquid (melting), liquid to gas (vaporization), or solid to gas (sublimation). ... When the pressure exerted on a substance increases, it can cause the substance to condense.
Explanation:
Hope it will help use
B)<span>Readily accept electron flow.</span>