Answer: After 7 years the number of birds of species A and B are same. and the number of birds during that year will be 140.
Step-by-step explanation:
Given: Sharon is conducting research on two species of birds at a bird sanctuary.
The number of birds of species A is represented by the equation below,where S represents the number of birds, x years after beginning her research.

The number of birds of species B is represented by the equation below,where S represents the number of birds, x years after beginning her research.

To plot the above function, first find points by which they are passing.
For species A, At x=0 , 
At x=2 , 
Similarly find more points and plot curve on graph.
For species A, At x=0 , 
At x=2 , 
Plot a line with the help of these two points.
Now, from the graph the intersection of curve (for A) and line (for B) is at (7,140) which tells that After 7 years the number of birds of species A and B are same. and the number of birds during that year will be 140.
Answer:
Use ≈ (approximately equal) sign as the scientific notation.
Step-by-step explanation:
(a) 0.001872 ≈ 0.0019
(b) 0.3411 ≈ 0.34
(c) 0.000845 ≈ 0.00085
*Zeros before non-zero numbers are not significant.
*Zeros appearing between two non-zero digits are significant.
Hope this helps!!
Remember, -(-x)=x because the negatives cancel out
so
when p=-6 and q=7
p+(-q)-3
-6+(-7)-3
-6-7-3
-13-3
-16