This is the concept of financial mathematics, the simple interest rate is given by:
S.I.=(PRT)/100
where:
P=principle=$2500
R=rate=5.5%
T=time=1 year
Hence;
S.I.=(5.5*2500.1)/100
=$137.5
Thus the total amount he had after 1 year will be:
2500+137.5
=$2,637.5
Answer is a, 57.49.
17.42-12.60-9.62= $-4.80+62.29=57.49
Answer:

Step-by-step explanation:
we know that
In an <u><em>Arithmetic Sequence</em></u> the difference between one term and the next is a constant, called the common difference
The formula for an Arithmetic Sequence is equal to

where
d is the common difference
n is the number of terms
a_1 is the first term of the sequence
In this problem we have

substitute



so
<u><em>Find the first ten terms</em></u>

For n=2 ----> 
For n=3 ----> 
For n=4 ----> 
For n=5 ----> 
For n=6 ----> 
For n=7 ----> 
For n=8 ----> 
For n=9 ----> 
For n=10 ----> 
The sequence is

The rate defines how much the portion is of the base.
The height of the tree is the sum of the part below the line parallel to the horizontal and the part above the line parallel to the horizontal.
Height of the part below the line parallel to the horizontal = 18 sin16° = 4.96 meters
Horizontal distance of the tip of the of the shadow from the tree = 18 cos16° = 17.30 meters
Height of the part above the line parallel to the horizontal = 17.3 tan68° = 42.83 meters
Height of the tree = 4.96 + 42.83 = 47.79 meters