A volcano is formed when magma (Lava) spews up from deep within the earth. After each eruption the Volcano gets bigger and bigger, so basically after periods of time the volcano will get larger. Lava will rise in cracks in the earth or weak spots in the earths crust. The pressure is relieved thus resulting in a volcanic eruptions it forms the new crust and then eventually builds up in that spot making a volcano. They also form in places called hot spots and various other places.
Answer : The Lewis-dot structure of
is shown below.
Explanation :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is, 
As we know that rubidium has '1' valence electrons, iodine has '7' valence electrons and oxygen has '6' valence electrons.
Therefore, the total number of valence electrons in
= 1 + 7 + 2(6) = 20
As we know that
is an ionic compound because it is formed by the transfer of electron takes place from metal to non-metal element.
Answer:
Static Friction.
Explanation:
Friction is the force that resists the relative motion between the surfaces sliding against each other.
Static friction is friction between objects that are not in relative motion with each other.
The coefficient of static friction, typically denoted as μs,
Static friction arises due to surface roughness( relative term)
The static friction force can be overcome by an applied maximum force
F max = μs x N
N= normal force
Any force smaller than F max attempting to slide one surface over the other is opposed by a frictional force of equal magnitude and opposite direction.
Any force larger than F max overcomes the force of static friction and causes sliding to occur.
This maximum force is sometimes called the limiting value also. Here that value is 75 N.