Lily really wants to know what her average stride is, so she walked 50 meters three times at a natural and even pace and recorded the situation in the table below. Please complete it.

=2 13÷3

=7 1 (step size).

50×3÷(70+72+7 1)

= 150÷2 13

≈ 0.7m;

Its form is as follows:

Distance/meter Average number of steps/meter (with one decimal place reserved) The first, second and third times are 70 72 765 438+0 765 438+0 000.7 (1). Visual observation and actual measurement: 49.5-45=4.5 (meters);

Step measurement and actual measurement:

49.5-0.7×70

=49.5-49

=0.5 (m).

A: The difference between the results of Lili's visual inspection and step measurement and that of rope measurement is 4.5 meters and 0.5 meters respectively.

(2) Measure the distance of 18m first, mark it, continue to measure 18m, mark it again, mark it again and continue to measure, write down the length of the third measurement, and add the lengths of these three measurements to get the distance.