list of many lists

I wish to multiply each element of List #1 to each element of List #2 to form List #3. I then wish to multiply each element of List #3 to each element of List #4. Can someone direct me to the necessary instructions?

List #1 - 0.5, 2, 4, 5, 8, 15
List #2 - 2, 4, 5, 7, 8, 15, 30

List #3 will be a list of 42 values

Thanks