Please help me solve any of these questions

1L=1000mL
3,331L=3,331,000mL

To go from L to mL, we can simply move the decimal 3 times to the right, as that essentially multiplies that number by 1000.

or we can solve it this way

1L            1000ml
=
3331L        x ml

Cross multiply
3331000=1x
divide both sides by 1
3,331,000=x

Answer=3,331,000mL