FIG. 1 is a front view of the design for a sofa;
FIG. 2 is a rear view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a right perspective view thereof;
FIG. 8 is a left perspective view thereof;
FIG. 9 is a right perspective view of the sofa in a partially reclined position;
FIG. 10 is a left perspective view of the sofa in a partially reclined position;
FIG. 11 is a right perspective view of the sofa in a fully reclined position; and,
FIG. 12 is a left perspective view of the sofa in a fully reclined position.
The dotted lines shown on the article represent topstitching. The broken line showing is included for the purpose of illustrating environment of the design and forms no part of the claimed design.