The terminal velocity $($dashed black line, linewidth$=1\mathrm{.}5).$

b$)$ Repeat a$)$ but using $20$ steps;

c$)$ Repeat a$)$ but using $50$ steps;

d$)$ Comment on the difference in the results.

Obs: analytical solution $v(t)=\frac{gm}{c}[1-e^{-c\frac{t}{m}}].$