If a vocal range is E2 through C6 and her head voice starts at B4...what type she?

Based on the information given, the singer has a vocal range of E2 to C6 and her head voice starts at B4, she is likely a mezzo-soprano.

The vocal range of a mezzo-soprano typically spans from A3 to A5, with the head voice starting around F#4 or G4. The singer's vocal range falls within the typical range of a mezzo-soprano, and the head voice starting at B4 is also consistent with this vocal type.

However, it's important to note that vocal classification is not an exact science and there can be variations between individual singers.