Answer:
1) Rizza's average speed is 27 km/h.
2) The distance between Barretto and Pampanga is 294 km.
3) Aaron's journey was 3.5 hours long.
Explanation:
1) Time taken to cove the distance = 20 minutes
60 minutes = 1 hour
So that, 20 minutes =
hours
=
hours
Distance covered = 9 km
But,
speed =

Rizza's average speed = 9 ÷

= 9 x 3
= 27 km/h
Rizza's average speed is 27 km/h.
2) Time taken = 3.5 h
the car's average speed = 84 km/h
Distance between Barretto and Pampanga = average speed x time taken
= 84 km/h x 3.5 h
= 294 km
The distance between Baretto and Pampanga is 294 km.
3) The uniform speed implies that Aaron did not accelerate during his journey.
Distance covered = 210 km
uniform speed = 60 km/h
time taken =

=

= 3.5 hours
Aaron's journey was 3.5 hours long.