The ornamental design for an exercisebottle with a fluid opening, as shown and described.
FIG. 1 is a perspective view of an exercise bottle with a fluid opening showing my design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a right side elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a perspective view of an alternate embodiment of an exercise bottle with a fluid opening showing my design, with the fluid opening shown in dotted lines.
The dotted line showing is for illustrative purposes only, and forms no part of the claimed design.