A milk tank is in the form of a cylinder whose radius is 1.5 m and height is 10.5 m.

$r=1.5 \mathrm{~m}$

$h=10.5 \mathrm{~m}$

Capacity of the tank $=$ volume of the $\operatorname{tank}=\pi r^{2} h=\frac{22}{7} \times 1.5 \times 1.5 \times 10.5=74.25 \mathrm{~m}^{3}$

We know that $1 \mathrm{~m}^{3}=1000 \mathrm{~L}$

$\therefore 74.25 \mathrm{~m}^{3}=74250 \mathrm{~L}$