Answer:
Explanation:
In 1789, Antoine Lavoisier published a list of 33 chemical elements. Although Lavoisier grouped the elements into gases, metals, non-metals, and earths, chemists spent the following century searching for a more precise classification scheme. In 1829, Johann Wolfgang Döbereiner observed that many of the elements could be grouped into triads (groups of three) based on their chemical properties. Lithium, sodium, and potassium, for example, were grouped together as being soft, reactive metals. Döbereiner also observed that, when arranged by atomic weight, the second member of each triad was roughly the average of the first and the third.[19] This became known as the Law of Triads.[20] German chemist Leopold Gmelin worked with this system, and by 1843 he had identified ten triads, three groups of four, and one group of five. Jean Baptiste Dumas published work in 1857 describing relationships between various groups of metals. Although various chemists were able to identify relationships between small groups of elements, they had yet to build one scheme that encompassed them all.[19]
I try to think of things that calms me down. If that doesn't work, I try to think of things that makes me happy. As I once read in a book, you can never get over your anger but you can calm yourself down by forgetting about it.<span />
Answer:
Explanation:
For anyone in UsaTestPrep it is D) appoint church positions The "investiture struggle" of the 11th and 12th centuries that took place between Pope Gregory VII and King Henry IV symbolized the struggle between the church and state over who had the power to appoint church positions. Pope Gregory VII later excommunicated King Henry IV over this issue and it led to a weakening in the Holy Roman Empire therefore it is D.
1) Centripetal acceleration: 
2) Centripetal force: 6942 N
Explanation:
1)
For an object moving in uniform circular motion (=circular motion with constant speed), the net acceleration is the centripetal acceleration, directed towards the centre of the trajectory and whose magnitude is given by
where
v is the speed
r is the radius of the circle
For the car in this problem, we have
v = 14 m/s is the speed
r = 50.0 m is the radius
Substituting, we find the acceleration:
2)
The net force acting upon the car is the centripetal force, also acting towards the centre of the circular path, and whose magnitude is given by
where
m is the mass
a is the centripetal acceleration
For the car in this problem, we have:
m = 1780 kg is the mass
is the acceleration
Substituting, we find the centripetal force:
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D) the ability to make things happen
Explanation:
Energy is simply defined as the ability to do work or to make things happen. Energy is important to all aspects of living and non-living things. Based on the law of conservation of energy "energy can neither be created nor destroyed but can be transformed from one form to another".
Different forms of energy exists such as heat, thermal, chemical, mechanical, sound, electrical, e.t.c
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