A radar sends a signal to an aircraft at a distance of 30 km away and receives it back after `2xx10^(-4)` second. What is the speed of the signal ?

Explanation

To solve the problem of finding the speed of the radar signal, we will follow these steps:

### Step 1: Understand the problem
The radar sends a signal to an aircraft that is 30 km away. The signal travels to the aircraft and then reflects back to the radar. We need to find the speed of the signal based on the time it takes for the signal to make this round trip.

### Step 2: Calculate the total distance traveled by the signal
The distance to the aircraft is 30 km. Since the signal travels to the aircraft and then back, the total distance (D) is:
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