Answer:
\Delta E=1.22\times 10^{-22}J
Explanation:
The energy of electron in any state is given by
here h is planck's constant n is state of electron L is the infinte potential well m is the mass of electron
We know that 
Potential well dimension = 
Mass of electron 
So energy required to electron to jump from ground state to 3rd state



A) 500 calories
B)5000 joules
C) 5 kilocalories
Answer is C
I have no idea what that is, but all of your answers right