Embedding problem. Let $I$ be the ideal of polynomial algebra $A=K^{[n]}$, such that $A/I$ is also a polynomial algebra with smaller number $k$ of variables. Is it true that $I$ is generated by $n-k$ variables of $A$.
Definition. Call an ideal of polynomial algebra coordinate-like if it us generated by some coordinates of a polynomial algebra.
I am interested in the following particular cases of the embedding problem.
Problem 1. Consider any polynomial algebra $A=K^{[n]}$ and its $k$ polynomials $f_1,..., f_k$. For a polynomial algebra $B=K[y_1,..., y_{n+k}]$ consider the morphism sending $ y_i$ to $n$ coordinates of $A$ for $i\leq n$ and $y_j$ to $f_{j-n}$ for $j>n$. It is obvious that kernethr kernel of this morphism is the ideal $I$ with $A/I\cong B$$B/I\cong A$. So is it coordinate-like?
Problem 2. If $I\subset J$ are two coordinate-like ideals of polynomial algebra $A$, is it true that $J/I$ is coordinate-like ideal of $A/I$?
It is obvious that these problems follow from the embedding problem, but are they true?