Answer:

Step-by-step explanation:
we know that
Heron's Formula is a method for calculating the area of a triangle when you know the lengths of all three sides.
so

where
a, b and c are the length sides of triangle
s is the semi-perimeter of triangle
we have

<em>Find the semi-perimeter s
</em>
s=
Find the area of triangle



simplify

A square root is a number that produces a specific number when multiplied by itself. Basically it's the same number multiplied by itself.
hope this helps:)
The rate of change is 16.8 million tons per year
<em><u>Solution:</u></em>
Given that, the world catch of fish in 1950 was 12 million tons and in 1955 it was 96 million tons
<em><u>The average rate of change is given by formula:</u></em>

Value in 1950 = 12 million tons
Value in 1955 = 96 million tons
Change in value = value in 1955 - value in 1950
Change in value = 96 million - 12 million = 84 million tons
Number of years = 1950 to 1955 = 5 years
<em><u>Substitute the given values in formula,</u></em>
<em><u></u></em>
<em><u></u></em>
Thus rate of change is 16.8 million tons per year
The answer is going to be6/8