Answer:
The value of L is 0.3 nm.
Step-by-step explanation:
Given that,
Energy

Transmission probability = 10⁻³
We need to calculate the value of L
We know that,
Formula of tunneling probability
....(I)
Where,
....(II)
Where, m = mass of electron


Put the value in equation (II)


From equation (I)






Hence, The value of L is 0.3 nm.