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.
Step-by-step 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.

28 is 4 times 7, so we will rewrite it like that.

7 is 7 times 7, so we will rewrite it like that.

So the simplest form is,
16)
s^1/4 * s^1/4 * s^1/4 * s^1/4 = s^(1/4 + 1/4+1/4+1/4) = s^4/4 = s
Answer is s
15) Answer is 1. (because any number to the 0 exponent is equal 1 , except 0)
17)
= (t^3/6)^2 = t^6/6 = t
Answer is t
Sorry I cannot help you I do not know the answer
21 89(33)222)
Step-by-step explanation:
first i did somthing and tgen i add so got the answer