Let \( (a+bx+cx^{2})^{10}=\sum\limits_{i=0}^{20} p_{i}x^{i},\; a,b,c\in \mathbb{N} \). If \( p_{1}=20 \) and \( p_{2}=210 \), then \( 2(a+b+c) \) is equal to:
\( 8 \)
\( 6 \)
\( 12 \)
\( 15 \)