In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.

Example input: This list contains the top 25 accounts with the most followers on the social photo-sharing platform Instagram. As of May 2018, the most followed user is Instagram's own account, with over 235 million followers. Selena Gomez is the most followed individual, with over 137 million followers. Ten accounts have exceeded 100 million followers on the site.
Example output: who has the maximum number of followers on instagram
Example explanation: The answer is talking about the Instagram accounts that have the most followers. The question asking about the maximum number of followers. So this is a good example.
Q: The history of artificial refrigeration began when Scottish professor William Cullen designed a small refrigerating machine in 1755. Cullen used a pump to create a partial vacuum over a container of diethyl ether, which then boiled, absorbing heat from the surrounding air. The experiment even created a small amount of ice, but had no practical application at that time.
A:
when was the first fridge invented and by whom