Perms and hair color. You can color hair that has been permed, but try to use a semi-permanent or 'no-ammonia' color instead of a normal permanent color (which uses ammonia and 20 volume peroxide). Have your hair permed first.
Mowing grass works best when the grass is dry, as grass tends to bend over from the weight of the rain, making it difficult to get a straight cut. It also clumps inside your mower cavity and on your lawn, which can lead to dead grass underneath the clumps if not raked promptly.
You can mow it when it's wet but it won't leave a good cut. The problem with mowing when wet is when the mower deck runs over the grass the leading edge of the deck pushes the grass down,if the grass is wet some of the blades stick to the ground and don't get cut.