Final Answer:
The expression for the time (Δt) the electron spent in the region is given by: Δt = 25% × part(b).
Step-by-step explanation:
In this problem, we are tasked with determining the time spent by an electron in a specific region. The expression for this time, denoted as Δt, is obtained by taking 25% of the result obtained in part (b) of the problem. This mathematical representation encapsulates the relationship between the percentage of the result in part (b) and the time spent by the electron in the given region.
To break down the expression further, let's consider the result from part (b) as a variable, say 'X'. Therefore, the expression becomes Δt = 0.25 * X, which is equivalent to 25% of X. This simple formula allows us to easily calculate the time without explicitly knowing the value of X. The coefficient 0.25 represents the fraction of the result in part (b) that corresponds to the electron's time in the specified region.
In summary, the derived expression Δt = 25% × part(b) succinctly provides the solution to the problem, offering a clear and concise representation of the time the electron spends in the given region in terms of the variables involved in the problem statement.