Answer:
150000000000 m
0.0000005 seconds
33.33 ns
Explanation:
Speed of electromagnetic waves through vacuum = 
Echo time = 1000 seconds
Echo time is the time taken to reach the object and come back to the observer
Distance = Speed×Time
Venus is 150000000000 m away from Earth
Time = Distance / Speed
Echo time will be twice the time
The echo time will be 0.0000005 seconds
Difference in time = Difference in distance / Speed
The accuracy by which I will be able to measure the echo time is 33.33 ns
<span>velocity is defined as the rate of change of displacement irrespective of the length of the path travelled while speed is the average rate of covering distance. but in the liming case where the instantaneous velocity is given as v=dx/dt where dx is the small displacement in a small interval dt, both the speed and velocity have the same magnitude and the direction of velocity is the direction of the tangent to the corresponding displacement-time curve.</span>
Speed = frequency * wavelength
the answer is b. it's commercially reprocessed
