What is the time interval from 10 hr. 20 min. a.m. to 3 hr. 15 min. p.m in hour unit?

• A. \(1\frac{{11}}{{12}}\)
• B. \(2\frac{{11}}{{12}}\)
• C. \(3\frac{{5}}{{12}}\)
• D. \(4\frac{{11}}{{12}}\)