most events like the rising and setting of the Sun were used a natural measurement of time until recently.
Solar time, which is based on the motion of the Sun, is not the only way of measuring time, however. One might keep track of the regular appearance of the full Moon. That event occurs once about every 29.5 solar days. The time between appearances of new moons, then, could be used to define a month.
One also can use the position of the stars for measuring time. The system is the same as that used for the Sun, since the Sun itself is a star. All other stars also rise and set on a regular basis.
Although any one of these systems is a satisfactory method for measuring some unit of time, such as a day or a month, the systems may conflict with each other. It is not possible, for example, to fit 365 solar days into 12 or 13 lunar months exactly. This problem creates the need for leap years
Read more: http://www.scienceclarified.com/Ti-Vi/Time.html#ixzz5e1E705sr
I abbreviated most of it but there is a ton more at this link if you still need more.
Hello!
Yes, it needs oxygen to metabolize sugars that, in the end, produce carbon dioxide (CO2).
The angular momentum of an electron in the third Bohr orbit of a hydrogen atom is given by mvr=3h÷2π
<h3>What is momentum?</h3>
Momentum is defined as the amount of motion occurring in something that is moving, or the force that drives something forward to keep it moving.
Bohr never assumed stable electronic orbits with the electronic angular momentum quantized as
l=mvr = 
Quantization of angular momentum means that the radius of the orbit and the energy will be quantized as well.
Bohr assumed that the discrete lines seen in the spectrum of the hydrogen atom were due to transitions of an electron from one allowed orbit/energy to another.
Learn more about momentum here:
https://brainly.in/question/38837394
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