To model the decline of the herd of elephants at a rate of 4% per year, we can use the exponential decay function. The general form for exponential decay is:
\[ y = y_0 e^{-kt} \]
where:
- \( y \) is the quantity after time \( t \),
- \( y_0 \) is the initial quantity,
- \( k \) is the decay constant, and
- \( t \) is the time in years.
However, since we want to express the function in terms of a simpler model:
The herd is declining by 4% each year, which means that 96% of the herd remains each year. We can express this as:
\[ y = 62(0.96)^t \]
In this case, \( 62 \) is the initial number of elephants, \( 0.96 \) represents the remaining percentage of the herd each year (100% - 4% = 96%), and \( t \) is the number of years.
Therefore, the correct function is:
\[ y = 62(0.96)^t \]
So the answer is:
y = 62(0.96)^t