The frequency of the radio wave is:

The wavelength of an electromagnetic wave is related to its frequency by the relationship

where c is the speed of light and f the frequency. Plugging numbers into the equation, we find

and this is the wavelength of the radio waves in the problem.
Answer:
<em>The initial speed of the sprinter was 2.2 m/s</em>
Explanation:
<u>Constant Acceleration Motion</u>
It's a type of motion in which the velocity of an object changes by an equal amount in every equal period of time.
The following relation applies:

Where a is the constant acceleration, vo the initial speed, vf the final speed, and t the time.
The sprinter speeds up from an unknown initial speed to vf=3 m/s in t=2 seconds with an acceleration of
.
To find the initial speed, we solve the equation for vo:

Substituting the values:



The initial speed of the sprinter was 2.2 m/s
I got no earthly idea! Sorry........
The correct answer is:
<span>Become positively or negatively charged
In fact, an insulator is a material where charges cannot move freely. Therefore, it can be positively or negatively charge (for example, if it is rubbed against another object, the insulator can remain with an excess of charge), but it cannot transfer charge to other objects.</span>
Answer:
λ = hv
If frequency is doubled :
λ = h × 2v
λ = 2hv
Thus wavelength is doubled