1. A person who is far-sighted has a near point of 45 cm. The distance between the lens of the person's eye and their retina is 1.7 cm. What is the magnitude of the focal length, |f|, of the corrective lens needed for this person to see an object 25 cm in front of their eye?
2. A soap bubble is made of a film of soapy water (n = 1.33) that is 300 nm thick and is surrounded on both sides by air (n = 1). What is wavelength (in air) of light will experience constructive interference inside the bubble (i.e., after passing through the film of soapy water)?