Find the sum or difference.
Ken swam for 2one-half hours on Friday and 1start fraction 11 over 12 end fraction hours on Saturday. What is the total amount of time he swam these two days?
A. start fraction 7 over 12 end fraction hour
B. 3Start fraction 5 over 12 End fraction hours
C. 4 hours
D. 4Start fraction 5 over 12 End fraction hours