Answer:
The time required to receive the echo at the transducer is 
Explanation:
Frequency of ultrasonic beam, f = 5 MHz
It reflects off an object 5 cm deep.
We need to find the time required to receive the echo at the transducer. The ultrasonic wave is an electromagnetic wave. it moves with a speed of light. Let t is the time taken by the wave to go once.
So,



Time to receive the echo at the transducer gets doubled. So,

Hence, this is the required solution.
The first one. if its not right im sorry.
hope this helps!!
C. Skin
Because it's the outer layer of your body that protects everything
Since he wants to minimize his monthly payment, he could get his machine from scratch and dent store, where they sell a nearly damaged goods ( such as small scratches), but the good's price will drop significantly.
Try to find the options with 'scratch and dent' on it
A is the correct answer found ww.cdc.ov