Recover plane-distance and coupled-motion parameters
\[\Pi:\ 2x-3y+6z=-4,\qquad P(\lambda)=\begin{pmatrix}2\\-1\\-2\end{pmatrix}+\lambda\begin{pmatrix}0\\0\\2\end{pmatrix}\]
Find every real λ for which the perpendicular distance from P(λ) to Π equals 1. Give the distinct count and ordered extreme values L≤U; if there is one value, enter it in both fields. Then find the perpendicular foot H on Π from P(L)