Chapter 4 - Exponential and Logarithmic Functions - Section 4.3 Exponential Functions - 4.3 Assess Your Understanding - Page 306: 53

See graph. domain $(-\infty,\infty)$, range $(0,\infty)$, H.A. $y=0$.

Step 1. To obtain the graph of $f(x)=e^{-x}$ from $y=e^x$, reflect the curve across the y-axis. See graph. Step 2. We can determine the domain $(-\infty,\infty)$, range $(0,\infty)$, horizontal asymptote H.A. $y=0$.