Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Zinc is active transition metal kind of metal.
Zinc is what kind of metal.?

Lipids are available to the body from three sources.
Lipids are available to the body from how many sources?

The human body has as many as two trillion lymphocytes, and lymphocytes make up about 25% of all of leukocytes.

The human body has as many as two trillion lymphocytes, and lymphocytes make up about 25% of all of what?