1) perpendicular
2) parallel
3)perpendicular
F= 6.
-7f -9=9-4f
3f-9=9
3f=18
F=6
First, It's a function.
Second, domain is {a,b,c,d}
Third, range is {x,y,z}
Reason why it's function because
1. A single value in Input doesn't have 2 lines connected (domain must not be repetitive.)
2. All Inputs have lines connected to Output (if not then not a function.)
The first question is probably around 12 cm. It looks to be about half of like AC. Then the third question would be a 90° angle I do belive
It will take 0.556 seconds for an echo to reach one's ears
<h3>Calculating the time to hear an echo</h3>
From the question, we are to determine how long it would take an echo to reach one's ears
From the formula,

NOTE: To hear an echo, the sound will travel to and fro, hence, it will cover twice the distance
From the given information,
Distance = 92.0 m
NOTE: Speed of sound in air at 0 °C ≅ 331 m/s
Putting the parameters into the formula, we get


Time = 0.556 secs
Hence, it will take 0.556 seconds for an echo to reach one's ears.
Learn more on Calculating the time to hear an echo here: brainly.com/question/16676723
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