Answer:
The value is 
Explanation:
From the question we are told that
The emitted frequency increased by 
Let assume that the initial value of the emitted frequency is

Hence new frequency will be 
Generally from Doppler shift equation we have that
![f_1 = [\frac{ v \pm v_o}{v \pm + v_s } ] f](https://tex.z-dn.net/?f=f_1%20%3D%20%20%5B%5Cfrac%7B%20v%20%5Cpm%20v_o%7D%7Bv%20%5Cpm%20%2B%20v_s%20%7D%20%5D%20f)
Here v is the speed of sound with value 
is the velocity of the sound source which is
because it started from rest
is the observer velocity So
Generally given that the observer id moving towards the source, the Doppler frequency becomes
=>
=> 
Answer:
It would be. Quarter dark
Explanation:
Sun's lights going all the way to the moon but there will still a dark part of it
it's obviously won't be neither complete light nor completely dark
so the right answer is: Quarter dark
Answer:
Since it us the resistance that causes the power output, it might be intuitive to think that more resistance produces more power but as P=I^2 * R one actually needs high current and low resistqnce. That means 75 W has lower resistance and higher current.
Now you may think that making the resistance very low, one gets the most power. Not so, as the circuit has wires, power source etc. All the have their resistance. In theory one gets the maximum power over a resistor when the resistor is half of the total resistance of the circuit. This in practice would be inefficient as one would lose half of the total power elsewhere. In practice circuits have fuses that limit the current and one gets the maximum power at the current the fuse is rated to. So if there is 20 A fuse, the maximum power is 2400 W and the corresponding resistance 6 ohm.
A the stamen :)). haha yea smert