Answer:
F (4h>18)
How To Do It:
She's walking at a rate of 4 miles per hour. Which means that you would be multiplying 4 by the amount of hours Liang walks(4h). The next part of the inequality is the sign and the other value. To get this from the equation we see that it says she must walk at least 18 miles. Meaning that the 4h will always be greater than the 18 that is on the other side.