1.  What is the average speed in mm$/$s through a $4\mathrm{.}0-$ mm $-$diameter tube of $2\mathrm{0\; }$C motor oil if the pressure gradient is $1700$  Pa$/$m $?$

2.  What is the average speed in mm$/$s through a $4\mathrm{.}0-$ mm $-$diameter tube of $100$ ^oC motor oil if the pressure gradient is $1700$  Pa$/$m $?$ 

Take the viscosity of motor oil to be $0\mathrm{.}24$ at $20$ degrees and $0\mathrm{.}008$ at $100$ degrees.