Which accidental is used in measure 15 and How does this accidental alter the original note

Oliver is out on location for a photo shoot. he prefers working with natural light. he has, however, realized that direct light is falling on the subject. how can oliver soften the natural light?

Ineed don't know what's in this tell class

Brought a new sophisticated and european influence to jazz piano and is today considered one of the most influential pianists of modern jazz. some of his more famous recordings are, sunday at the village vanguad and waltz for debby. he drew influences from the french impressionist composers claude debussy and maurice ravel, as well as bebop pianist bud powell. his playing can be described as lyrical, sensitive, and introspective yet with an underlining commitment to swing.