Here barrel of tomato sauce has spilled on a tile floor.
The function
represents how the sauce is flowing, where, 't' represents time in minutes, and 'r' represents how far the sauce is spreading.
The spilled sauce is creating a circular pattern on the tile and the area of pattern is expressed as

A. Now we have to find the area of circle of spilled sauce as a function of time:
.
Now, we know that

and

plugging the value of 'r' as function of time in the area of the pattern, we get:

So the area of the circular pattern as a function of time is given as:

B. We have to find how large is the area of spilled sauce after 5 minutes.
plugging the value of 't' in the equation of the area as a function of time,

we get:

(we have taken
)
Therefore,
square units