Emma operates a lemonade stand on weekends. She currently sells 30 glasses of lemonade per day at a price of $3 per glass. She buys lemons from the grocery store for $1 each. It takes 20 lemons to make one pitcher of lemonade and one pitcher is enough to fill 10 glasses. The wood Emma used to construct the stand cost $60, and the glasses and pitchers cost $70. Emma considers her own time to be worth $50 per day, and would not want to run the lemonade stand if she was earning less than that. Which of the following choices would make Emmas lemonade stand profitable on a daily basis?

Hiring her younger brother to run the lemonade stand for $40 per day.

Using disposable cups instead of reusable glasses. Disposable cups each cost $0.1.

Increasing her sale price to $4 per glass, though if she does this she only thinks she will sell 20 glasses per day.

Buying lemons in bulk at a price of $15 per bag of 30 lemons.