What are the measures that countries take to prevent the entry of illegal migrants into their States?

Click the item in the left column. use the plus sign to move it up or the minus sign to move it down until it matches the correct entry in the right column. lock your answer in place by clicking the square beside the item. (a checkmark means it is locked.) amazon basin a atacama desert b andes mountains c lake titicaca d peru e patagonia f brazil g chile h suriname

Distance that lewis and clark traveled from st. louis to ft. clatsop near the pacific ocean.

What are the answers for the following questions?