Answer:
Frequency, 
Explanation:
Visible red light has a wavelength of 680 nanometers (6.8 x 10⁻⁷ m). The speed of light is 3.0 x 10 ⁸ m / s. What is the frequency of visible red light?
It is given that,
Wavelength of a visible red light is, 
Speed of light is, 
We need to find the frequency of visible red light. It can be calculated using below relation.

So, the frequency of visible red light is
.
He produced the first orderly arrangement of known elements, he used patterns to predict undiscovered elements
The correct answer is<span> B.The speed of sound in air is directly proportional to the temperature of the air.
When the temperature increases so does the speed of sound. Sound is faster by </span>0.60 m/s for every higher degree in air temperature because the air density is reduced and the sound can travel faster.
<em>An is formed when an atom loses or gains one or more electrons. Because the number of electrons in an ion is different from the number of protons, an ion does have an overall electric charge. Consider how a positive ion can form from an atom. The left side of the illustration below represents a sodium (Na) atom</em>
Kinematics : Study of motion
Fluid kinematics : study of how fluid flows and how to describe its motion.
There are two ways to describe fluid motion
one is Eulerian, where the variations are described at all fixed stations as a function of time.
the other is Lagrangian, in which one follows all fluid particles and describes the variations around each fluid particle along its trajectory.
<u>DIFFRENCE BETWEEN LAGRANGIAN AND EULERIAN:</u>
1.Both Lagrangian and Eulerian describes time variation.
2. Eulerian describes the rate of change in one point of space
Lagrangian descries rate of change of a property of material system.
To know more about the Lagrangian and Eulerian :\brainly.com/question/14944792
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