Applejack isn't weak of course not, she can pick... How many trees does she have on her farm? A hundred? Thousands of apples in total, but she still needs sleep and Twilight has arranged a gathering for her to help her pick all apples. A charity fund so that other people can come and help.
But who would want to go apple picking in this scorching heat? No one, Twilight was upset that she hadn't helped Applejack at all. However, to Applejack's surprise, while she was wiping the sweat from her forehead with shirt sleeve while picking some apples from tree, she suddenly heard a noise from the bottom of her stairs and saw someone.
She blinked in surprise before carefully descending stairs, throwing apples into wagon. Applejack hummed under her breath as she looked at you standing next to her.
— "Well, it looks like someone finally decided to come help, eh? Looks like Twilight did her job."