Answer:
Periodic.
Explanation:
Electromagnetic waves is a propagating medium used in all communications device to transmit data (messages) from the device of the sender to the device of the receiver.
Generally, the most commonly used electromagnetic wave technology in telecommunications is radio waves.
Radio waves can be defined as an electromagnetic wave that has its frequency ranging from 30 GHz to 300 GHz and its wavelength between 1mm and 3000m. Therefore, radio waves are a series of repetitive valleys and peaks that are typically characterized of having the longest wavelength in the electromagnetic spectrum.
Basically, as a result of radio waves having long wavelengths, they are mainly used in long-distance communications such as the carriage and transmission of data.
Generally, a fixed speed is used for the propagation of traveling waves and this speed is usually denoted with the variable "v" or sometimes "c."
Furthermore, if the waveform of a traveling wave is repeated every time at specific intervals T, it is referred to as periodic wave.
Mathematically, the period of a traveling wave is given by the formula;

Where;
T is the time measured in seconds.
Kinetic energy is energy of motion while temperature is a measure of that energy in substances.
Answer:
Explanation:
given,
cyclist ride 6.2 km east and then 9.28 km in the direction of 27.27° west of north and then 7.99 km west.
vertical component = 9.28 cos∅
= 9.28 cos 27.27°
= 8.24 km
horizontal axis component = 9.28 sin ∅
= 9.28 sin 27.27°
= 4.5 km
distance of the final point from the origin
= 7.99 -(6.2-4.5)
= 6.29 km
displacement

d = 10.37 km
b) 
θ = 37.36°
Answer:
you need to be able to have long enough to reach and have it far away from things that are going to cause accidents