
Those reaction in which two or more substances combine to form a one new substance are called Combination reaction
In this reaction, We can add :
- Two or more elements can combine to form a compound.
- Two or more compounds can combine to from a one new compound.
- An element and a compound can combine to form a new compound.


In this, Hydrogen is an element and Oxygen is another element. Both are combined to form compound 'Hydrogen oxide'. Hydrogen oxide is commonly known as water.
I would say a short person with muscles considering they are closer to the ground, but they may not be able to build up as much force in such a short time compared to the tall person.
Short Answer- Friction
Explanation- There is friction between the grass and the ball. Friction is a type of force that limits motion between two surfaces that are touching. Friction is the force that one surface exerts on another with the two surfaces rubbing together.
This is the answer, hope it helps :)
Magma is a molten and semi-molten rock mixture found under the surface of the earth. and i think silica is the most abundant. hope it helps.sorry if it's uncorrect. :)