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.
Of the many processes involved in the water cycle, the most important are evaporation, transpiration, condensation, precipitation, and runoff. Although the total amount of water within the cycle remains essentially constant, its distribution among the various processes is continually changing.
Answer:
On the picture are all principles cited on wikipedia.
Explanation:
So the answer is
1. Environment must be exploited to improve living standards
2. Flourishing human and nonhuman life depends on diversity of life forms
When we go to periodic table, Sulfur is
an element that has 16 protons and 16 electrons.
when there is 18 electrons, with number of two electrons more than protons. This makes it an ion and
the ion has a -2 charge.
So when there is16 protons, 18 neutrons, and 18 electrons the symbol is S⁻².
The neutrons have no charge but they add only mass to the
elements. So when there is 16 neutrons, it doesn't change the symbol of ion.
