There are 1 questions in this calculation: for each question, the 1 derivative of p is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 20 - 2p\ with\ respect\ to\ p：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - 2p + 20\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - 2p + 20\right)}{dp}\\=& - 2 + 0\\=& - 2\\ \end{split}\end{equation} \]

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