Observe the table.

The function is an increasing function with in the time interval $\"\"$ .

Upper estimation is the approximation by taking right end points with subintervals $\"\"$ and

Lower estimation is approximation by taking the left end points subintervals $\"\"$ .

In the table, time interval is divided into six sub intervals.

Therefore, the number of subintervals $\"\"$ .

Width of the each interval : $\"\"$ .

Lower estimate :

Left end points are $\"\"$ and $\"\"$ .

Lower estimate for distance travelled in $\"\"$ seconds is

$\"\"$

Lower estimate for distance traveled in $\"\"$ seconds is $\"\"$ ft.

Right end points are $\"\"$ and $\"\"$ .

Upper estimate for distance travelled in $\"\"$ seconds is

$\"\"$

Upper estimate for distance traveled in $\"\"$ seconds is $\"\"$ ft.

Lower estimate for distance traveled in $\"\"$ seconds is $\"\"$ ft.

Upper estimate for distance traveled in $\"\"$ seconds is $\"\"$ ft.