(1) While in a ski area, each skier shall do all of the following:

    (a) Maintain reasonable control of his or her speed and course at all times.

    (b) Stay clear of snow-grooming vehicles and equipment in the ski area.

    (c) Heed all posted signs and warnings.

    (d) Ski only in ski areas which are marked as open for skiing on the trail board described in section 6a(e).

    (2) Each person who participates in the sport of skiing accepts the dangers that inhere in that sport insofar as the dangers are obvious and necessary. Those dangers include, but are not limited to, injuries which can result from variations in terrain; surface or subsurface snow or ice conditions; bare spots; rocks, trees, and other forms of natural growth or debris; collisions with ski lift towers and their components, with other skiers, or with properly marked or plainly visible snow-making or snow-grooming equipment.