There is no scientific evidence to suggest that celery increases semen volume. Semen volume is primarily influenced by factors such as age, overall health, and hydration levels. Eating a healthy diet that includes celery may have some benefits for men's sexual health due to its high nutrient content, but it is unlikely to directly impact semen volume.

There is no specific volume of semen that is deemed ideal for fertilization in mathematics. Fertility is influenced by various factors beyond semen volume, such as sperm count, motility, and morphology. It is recommended to focus on overall sperm health rather than just volume.

A vasectomy does not affect the volume of semen produced by the body. However, after a vasectomy, semen will no longer contain sperm, as the procedure blocks the vas deferens, preventing sperm from being included in the ejaculate.

In average 3ml / ejaculation.

Semen is the total ejaculate. The sperm content in the ejaculate is a tiny part (about 5% of the total volume, the rest is lubricating fluids and nourishment for the sperm while it is on its way.

Semen content and semen volume would be two different things & your question is ambiguous.

If the sperm content of the semen is low you wouldn't be able to conceive children. If the volume is low, you just wouldn't have much ejaculation. you could still have an orgasm, just wouldn't be much semen there.