In what 2 ways does the American electoral system tend to promote a two-party system?

How does the electoral system encourage a two-party system? ... voters elect the state party's delegates that will go to their political party's national convention to select the party's candidate.

Explanation:

ww1 weapons: tank. tanks were used for the first time in the first world war at the battle of the somme. they were developed to cope with the conditions on the western front. the first tank was called 'little willie' and needed a crew of 3.