Answer:
92.25m
Explanation:
In order to solve the exercise, it is necessary to apply the concept of construtive interference due to a path difference.
The formula is given by,

where,
n is the index of refraction of the medium in which the wave is traveling
wavelenght
is the path difference
m = integer (0,1,2,3...)
Since in this case we are dealing with an atmospheric environment, where air is predominant, we approximate n to 1.
And since we need the reflected wave,

Where x is the distance in one direction without return.
The distance must correspond to the minimum therefore m = 0, so



Then the minimum distance is:



Therefore the minimum distance from the mountain to the receiver that produces destructive interference at the receiver is 92.25m
Answer:0.8 meter
Explanation:
Frequency=426.7hz
Velocity=346m/s
Length =velocity ➗ frequency
Length=346 ➗ 426.7
Length =0.8
The wording of the choices is really unclear. With two resistors in parallel,
here's the situation:
-- The voltage across each resistor is the same as the voltage across
the other one. If the parallel combination is connected to the battery,
then the voltage across each resistor is the full battery voltage.
-- The current through each resistor is (V) / (the resistance of that resistor).
That's the same current as would flow through that resistor if the other one
were not there.
-- As long as the battery or other power supply holds out, neither of these
quantities changes.
Can you match this situation to one of the choices listed ?
It looks to me as if choice 'C' is the one that's most likely
trying to say this.