Yes, but first lightly sand the surface to remove any gloss.
I would use Kilz latex primer.
Not directly. You will need to use a primer made to adhere to oil and will accept a latex topcoat.
You can use either a water or oil-based paint over a latex primer.
Enamel is a word used to describe a finish, not the formulation of a paint. It simply means a hard reflective surface. Many people mistakenly use the word enamel when referring to oil based paints. So. if you are asking if you can paint latex or acrylic paint over a latex or acrylic enamel the answer is yes, however, I strongly recommend you sand the old paint first to give the top coat "tooth". If you are asking about painting latex or acrylic over an oil based paint the answer is still yes, however you must first sand the old paint and apply a good quality primer to it. Check with a reputable paint retailer for the best brand in your area.
You can use either enamel (oil-based) paint or latex (water-based) paint. If you are using latex paint, you need to use a primer (undercoat) first. The paint store will have a special primer that allows you to paint latex over enamel. If you are going to do this, it is also a good idea to either sand the enamel paint before you paint over it, or wash it with TSP (trisodium phosphate) cleaner to remove the gloss.
Do you mean oil based enamel, or alkyd enamel? It can, but you will have to prime it with a barrier coat of compatible primer for the new paint to stick to it. I would not recommend it though. If the latex paint has been around for a long time, you have a better chance of having your new paint last. Is this inside or outside? Is it exposed to temperature extremes? The latex paint will be able to expand and contract more than the oil based enamel. If you can imagine putting paint on a latex glove, letting it dry, then putting the glove on (stretching it) then you will have a good idea (although much more extreme) of what you are asking the paint to do. If you really must put an oil based enamel on top of latex. Use a good oil based enamel like Kilz or Zinnzer Bullseye before you paint it. After you put the barrier coat on, you will have a limited time to get the other paint on....check the directions.
Mineral oil destroys latex. Other oils are not good for latex.
Scuff them up with steel wool or sand paper first. Oil paint can be put on directly. Enamel latex should adhere alright. For regular latex I would use an oil based primer first.
Latex-based paints are not likely to stick to fiberglas particularly well. You'll most likely have better results from an oil-based paint.
Yes, some do use that.
Latex paint will go over WD40 but will not adhere. I work at paint stores and we spray our mixing tables with WD40 so that the paint cans will slide easily and any spilled or splashed paint will peel off if dried.
Yes, it is possible to use latex paint over oil-based primer, but it is important to ensure proper adhesion by lightly sanding the primer before applying the latex paint.