To determine the correct graph for the exponential decay modeled by the equation \( y = 4,060(0.95)^t \), we should first calculate the number of birds at the specified years (0, 5, 10, 15, and 20).
Here are the calculations:
-
At \( t = 0 \):
\[
y = 4,060(0.95)^0 = 4,060 \times 1 = 4,060
\]
-
At \( t = 5 \):
\[
y = 4,060(0.95)^5 \approx 4,060 \times 0.77378 \approx 3,141.12
\]
-
At \( t = 10 \):
\[
y = 4,060(0.95)^{10} \approx 4,060 \times 0.61391 \approx 2,487.48
\]
-
At \( t = 15 \):
\[
y = 4,060(0.95)^{15} \approx 4,060 \times 0.46329 \approx 1,882.83
\]
-
At \( t = 20 \):
\[
y = 4,060(0.95)^{20} \approx 4,060 \times 0.34868 \approx 1,415.93
\]
Now, compiling the results in a table:
Years (t) | Number of Birds (y)
------------------------------
0 | 4,060
5 | ~3,141
10 | ~2,487
15 | ~1,883
20 | ~1,416
Now, we look at the responses provided to match this sequence:
-
The first response shows a decreasing pattern ranging from 0 to 600 on the y-axis, which is not suitable for our values.
-
The second response has a y-axis from 0 to 6000, which is also not suitable.
-
The third response portrays a decreasing pattern from around 40,000 to 52,000, which does not correspond to our calculated values.
-
The fourth response shows a decreasing curve with a y-axis from 0 to 6000, which, although not exact, could potentially encompass values around \( 1,416 \).
Given the calculations, the correct response would most likely be the fourth option, as it shows a decreasing trend and can cover the calculated values, contingent on the axis scaling.
Without seeing the exact graphs, it's difficult to give a definitive answer, but based on the information provided, the fourth graph appears to be the most appropriate choice.