revolution
rotation
universal gravitation
Answer:
retrograde motion
Explanation:
All the planets have direct motion or progade motion i.e. they move in eastward direction around the Sun. The exceptions are Venus and Uranus which apparently move westwards. This is type of motion is known as retrograde motion. Venus and Uranus move opposite to the other planets motion against the background of stars.
Answer:
retrograde motion
Explanation:
Select one:
a. KF
b. MgF2
c. NO2
d. Na2S
b. 17
c. 19
d. more information is needed to figure this out.
Answer:
c. 19
Explanation:
Potassium is a chemical element of the periodic table whose chemical symbol is K, whose atomic number is 19. It is an alkaline metal of white-silver color, which abounds in nature in the elements related to salt water and other minerals. It oxidizes rapidly in air, is very reactive, especially in water, and chemically resembles sodium. It is an essential chemical element.
The K having an atomic number of 19 means that it has 19 protons and in normal conditions for a neutral atom it will have 19 electrons, and being one step away from argon gas makes it extremely unstable.