Ranges of floating point datatype in C?

Question

I am reading a C book, talking about ranges of floating point, the author gave the table:

Type     Smallest Positive Value  Largest value      Precision
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Answer 1

It's a consequence of the size of the exponent part of the type, as in IEEE 754 for example. You can examine the sizes with FLT_MAX, FLT_MIN, DBL_MAX, DBL_MIN in float.h.