Answer:
Her return is

Explanation:
From the question we are told that
The number of shares purchased is

The cost price of each share is

The limit order is

The first market price for each share is

The second market price for each share is

The third market price for each share is

Generally the limit order would not be executed given that it is higher than the market opening and closing price.
Considering Rebecca's initial investment of $ 20 per share, her return is mathematically evaluated as

Here d stands for the dividend but since we are told that the stock did not pay any dividend

