Don’t eat such tomatoes! It's dangerous!

See black, sunken spots on the blossom end of your tomatoes? It's a sure sign of blossom-end rot.
Never eat such tomatoes, even if you cut out dark spots. It's dangerous. Discard them. I
Now I'll tell you how to tackle this issue and save your tomatoes. Prepare a simple yet efficient fertilizer.
You'll need one cup of wood ash, one cup of 9% vinegar and 10 liters of water.
Put ash into a bucket, then add vinegar, and then water.
Use this solution to fertilize tomatoes, adding one or two liters per plant.
After such fertilizing, tomatoes will be healthy and give abundant yield.
May you prosper!