As a consultant to a theme park, your job is to ensure the safety of the children's rides. You are able to calculate the net force of the roller coasters acting on a 16 kg child over time given a few select data points. At t = 18.48s the position was < 4.53, 2.25, -11.82 > m.
At t = 18.53s the position was <3.5100000000000002, 3.2600000000000002, -11.950000000000001 > m.
At t = 18.580000000000002s the position was <3.99, 3.95, -10.33 > m.

In the first time interval, from 18.48 to 18.53s, what was the average momentum?