two questions: A) list length of solve result, B) 0^0

I have the following stripped down test case,

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$ maxima -b solve-result.max
Maxima 5.15.0 http://maxima.sourceforge.net
Using Lisp SBCL 1.0.11.debian
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i1)                       batch(solve-result.max)

batching /home/user/solve-result.max
(%i2)                       solve([c11 = 0], [c11])
(%o2)                              [c11 = 0]
(%i3)                solve([c12 = 0, c22 = 0], [c12, c22])
(%o3)                        [[c12 = 0, c22 = 0]]
---------------------------------------------------------------

in my application a function generates a set of equation and variables
which are fed to solve. I don't know the variables a priori.

Question 1:
Both have obviously length 1, how can I differentiate both cases?
Is it possible to remove the other brackets in the second case?

and here the next one, 

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$ maxima -b bernstein.max
Maxima 5.15.0 http://maxima.sourceforge.net
Using Lisp SBCL 1.0.11.debian
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i1)                        batch(bernstein.max)

batching /home/user/bernstein.max
(%i2)                          display2d : false
(%o2) false
(%i3) my_bernstein(n,k,x):=binomial(n,k)*(x+1)^k*(1-x)^(n-k)
(%o3) my_bernstein(n,k,x):=binomial(n,k)*(x+1)^k*(1-x)^(n-k)
(%i4) my_bernstein(0,0,1)
0^0 has been generated
#0: my_bernstein(n=0,k=0,x=1)(bernstein.max line 0)
 -- an error.  To debug this try debugmode(true);
--------------------------------------------------------------


Question 2:
Experimenting with Bernstein polynomials,
0^0 is triggered but here, 0^0 = 1, can safely be assumed.
Is it possible to suppress this error?

Andre