Answer:
0.50 seconds
Step-by-step explanation:
The time it takes for an echo to return is the time it takes for the sound to make the round trip between the source and the reflecting object.
The boulder is 80 m away from the source, so the round-trip distance is 2×80 m = 160 m. At a speed of 320 m/s, it takes sound ...
(160 m)/(320 m/s) = 0.50 s
to make the round-trip.
It will take 0.50 seconds to hear the echo.
Answer:
They aren't equivalent
Step-by-step explanation:
Look at them as simplified fractions
4/18 = 2/9
2/12 = 1/6
If both of these are in their most simplified forms then its not equivalent!
Answer:
Length = 34
Step-by-step explanation:
Perimeter of rectangle = a+a+b+b = 2(a+b)
Let a = length = 2b - 4
Let b = width
Therefore
(2b-4) + (2b-4) + b + b = 106 cm
Bracket off
2b-4+2b-4+b+b = 106cm
Collect like terms
2b+2b+b+b-4-4 = 106cm
6b-8 = 106
6b = 106+8
6b = 114
b = 114÷6
b = 19
To get a
2b - 4
2(19) - 4
38-4
= 34
He is going to need at least 6 more dump trucks of dirt. 5 will be completely full, and the last one will have to be at least 88% full.
