Final answer:
The maximum number of electrons in any shell is given by the formula 2n², which equals 32 for the fourth shell (n=4).
Step-by-step explanation:
The maximum number of electrons found in any shell of the known elements is determined by the formula 2n². For the highest occupied shells in naturally occurring elements, this means the maximum number of electrons in a shell is 32. This can be calculated for the fourth shell (n=4) where the number of electrons is 2(4²) = 2(16) = 32. However, it's important to note that not all shells reach this maximum in naturally occurring elements due to their electronic configurations.