There are 1 questions in this calculation: for each question, the 1 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 7 - \frac{2t}{3}\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - \frac{2}{3}t + 7\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - \frac{2}{3}t + 7\right)}{dt}\\=& - \frac{2}{3} + 0\\=& - \frac{2}{3}\\ \end{split}\end{equation} \]

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