The graph shows the path of light from a wall reflecting off mirrored ceiling tiles, where x is the distance from the wall in feet and y is height in feet along the wall where the light source hangs.

Which statement describes the room based on the graph?
The ceiling is 10 feet high.
The ceiling is 20 feet high.
The light source is 10 feet off the ground.
The light source is 20 feet off the ground.

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?