Answer:
t= 8.7*10⁻⁴ sec.
Explanation:
If the signal were able to traverse this distance at an infinite speed, the propagation delay would be zero.
As this is not possible, (the maximum speed of interactions in the universe is equal to the speed of light), there will be a finite propagation delay.
Assuming that the signal propagates at a constant speed, which is equal to 2.3*10⁸ m/s (due to the characteristics of the cable, it is not the same as if it were propagating in vaccum, at 3.0*10⁸ m/s), the time taken to the signal to traverse the 200 km, which is equal to the propagation delay, can be found applying the average velocity definition:

If we choose x₀ = 0 and t₀ =0, and replace v= 2.3*10⁸ m/s, and xf=2*10⁵ m, we can solve for t:

⇒ t = 8.7*10⁻⁴ sec.
Answer:
The drill down term is basically used in the information technology for the explore the multidimensional information or data by navigating the different layers of the data from the web page applications.
Drill down basically involve in the database by accessing the specific information through the database queries. Each query basically increase the data granularity. This term is also involve with the link for represent the details more specifically.
The drill down is the simple approach or technique for dividing the complex problems into small parts so that it make the technique more efficient.