What's an example of a task that requires knowledge of physical objects to perform?
Remove permanent marker off skin.

What's an example of a task that requires knowledge of physical objects to perform?
how do you fill out a captcha on mturk?

What's an example of a task that requires knowledge of physical objects to perform?
How to remove smells from a musty basement or other lingering odors.

What's an example of a task that requires knowledge of physical objects to perform?
How do I hang a picture frame?