Please find the attached diagram for a better understanding of the question.
As we can see from the diagram,
RQ = 21 feet = height of the hill
PQ = 57 feet = Distance between you and the base of the hill
SR= h=height of the statue
=Angle subtended by the statue to where you are standing.
= which is unknown.
Let us begin solving now. The first step is to find the angle
which can be found by using the following trigonometric ratio in
:

Which gives
to be:

Now, we know that
and
can be added to give us the complete angle
in the right triangle
.
We can again use the tan trigonometric ratio in
to solve for the height of the statue, h.
This can be done as:





Thus, the height of the statue is approximately, 8.45 feet.
If you have a picture of the problem I can answer it so just send a pic of the math problem
Answer: 
Step-by-step explanation:
Since, The total number of student = 300
Out of which,
The number of students who are only in Maths = 120
And, The number of students who are only in Science = 50
While, the students who are not from any subject = 100
Hence, the number of student who are from both maths and science = Total student - Maths student (only) - science student (only) - None
= 300 - 120 - 50 - 100
= 30
That is, there are 30 students who are both from science and maths,
Thus, the probability of selecting one student who is both from maths and science = 30/300 = 1/10