There are 1 questions in this calculation: for each question, the 4 derivative of r is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ \frac{2000}{r} + π{r}^{2}\ with\ respect\ to\ r：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{2000}{r} + πr^{2}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{2000}{r} + πr^{2}\right)}{dr}\\=&\frac{2000*-1}{r^{2}} + π*2r\\=&\frac{-2000}{r^{2}} + 2πr\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-2000}{r^{2}} + 2πr\right)}{dr}\\=&\frac{-2000*-2}{r^{3}} + 2π\\=&\frac{4000}{r^{3}} + 2π\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( \frac{4000}{r^{3}} + 2π\right)}{dr}\\=&\frac{4000*-3}{r^{4}} + 0\\=&\frac{-12000}{r^{4}}\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( \frac{-12000}{r^{4}}\right)}{dr}\\=&\frac{-12000*-4}{r^{5}}\\=&\frac{48000}{r^{5}}\\ \end{split}\end{equation} \]

Your problem has not been solved here? Please take a look at the  hot problems ！