The black crust on the face of a cat, what it is (photo ) ?

We breed British Shorthair cat, appearing periodically on the face black scab. Scab, right there where the mustache grow. It is not dirt as straight as a crust. Sorry cat. What it is?how to treat?somebody was such ?The photo can be seen a little brown - dark spots near the mustache

Why pear rot from the inside directly on the tree ?

Externally

pears entirely normal, beautiful, but you start to eat, but they are rotten. What is it?And how can we deal with it?

Can the animal turn gray from stress or fear ?

whether after a fall from a high floor, for example, change color of the cat ?hair turn gray ?

At what age did the cactus appear " kids " ?

I have a couple of small cactus, well, one of them 5 years, I've heard that the " kids " are formed from already mature plants, even the old, in which about age ?

What is the thorny weed, thistle -like ?

Only he

not spotted , like milk thistle, but blooms almost as , moreover, as they say, - good honey plant .