Answer:
[tex] the \: average \: speed \: of \: the \: boat \: between \: 4 \: and \: 6 \: \\ minutes \: = \frac{1000 - 500}{6 - 4} = \frac{500}{2} = 250[/tex]
note: cant really see the measuring units for clear unit for the value, however the average speed is 250 meter/mins, from observation.
