
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.
Answer:
It takes total 248 years for Pluto to orbit the sun.
A) 
The magnitude of the capacitive reactance is given by

where
is the angular frequency
C is the capacitance
While the magnitude of the inductive capacitance is given by

where L is the inductance.
Since we want the two reactances to be equal, we have

So we find

B) 7449 rad/s
In this case, we have
is the inductance
is the capacitance
Therefore, substituting in the formula for the angular frequency, we find

C) 
Now we can us the formulas of the reactances written in part A). We have:
- Capacitive reactance:

- Inductive reactance:
