Answer:

The weed grows at a rate of 0.5 feet per day.
Step-by-step explanation:
The weed grows at a rate of 0.25 inches per hour.
And we want to convert this rate into feet per day.
We have that:

We knowt that there are 12 inches in one foot.
And since we want to cancel the inches, we can write our conversion factor as ft / 12 in.
We also know that there are 24 hours in one day.
And since we want to cancel the hours, we can write our conversion factor as 24 hr / day.
Hence:

Multiply and cancel common terms. So:

The weed grows at a rate of 0.5 feet per day.