To find height $ h $ use formula:
$$ V = \dfrac{ r ^{ 2 } \cdot h \cdot \pi}{ 3 } $$After substituting $ V = 3.14 $ and $ r = 1 $ we have:
$$ 3.14 = \dfrac{ 1 ^{ 2 } \cdot h \cdot \pi}{ 3 } $$$$ 3.14 \cdot 3 = 1 ^{ 2 } \cdot h \cdot \pi $$$$ 9.42 = 1 \cdot h \cdot \pi $$$$ h = \dfrac{ 9.42 }{ 1 \, \pi} $$$$ h = 2.9985 $$