Answer:
Average speed = (2x+3y)/5 miles/hour
Explanation:
Average speed is the total distance travelled per unit time.
Average speed = total distance/total time taken
Given;
1. Travelled x miles per hour for 2hours.
2 travelled y miles per hour for 3 hours.
Distance covered is;
1. Distance = speed × time
d1 = x × 2 = 2x
2. d2 = y × 3 = 3y
Total distance travelled = d1+d2 = 2x + 3y
Total time taken = t1+t2 = 2+3 = 5hours
Average speed = (2x+3y)/5 miles/hour
The correct answer is: rock 1000 and bottle of soda 2000
Answer:

Explanation:
P = Acoustic power = 63 µW
r = Distance to the sound source = 210 m
Acoustic power

Threshold intensity = 
Ratio

Ratio of the acoustic intensity produced by the juvenile howler to the reference intensity is 113.68
Answer:
An indirect measurement of the speed of molecules is temperature