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.
It is possible that she has a <span>cerebrospinal meningitis.
</span><span>Cerebrospinal meningitis affects the brain, spinal cord and the other peripheral parts of the nervous system.
Also the sensory neurons may arise in some deficiency. Sensory neurons are the neurons responsible for receiving the information from the environment or the stimuli. This sensory neurons pass the message thru interneurons and then to Central Nervous System (brain and spinal cord) which then sends the signal to the motor neuron. </span>
Answer:
Reticular activating system
Explanation:
The reticular formation refers to the network of neurons formed through the neurons of the brainstem and medulla.
The reticular system is not an anatomical structure but is present in the brainstem of the brain. The reticular formation on the upper side form the reticular activating system and on the lower side has the nerve fibres of the spinal cord.
The reticular system controls the consciousness ad arousals like mood and sleep.
In the given question, the sleep of the professor, therefore, could be due to the slow firing in the reticular formation.
Thus, Reticular activating system is the correct answer.
Reticular formation- brain stem structure associated with sleep, arousal, attention
Nutrients and waste both enter and leave cells through a process called Diffusion. :3