Why is a system of currency exchange necessary for international trade? a) nearly all world currencies are worthless on the world market. b) those buying goods on the world market only accept payment in gold and silver. c) most goods bought on the international market must be bought and paid for using united states dollars only. d) there must be a way to pay for goods purchased from countries with different types of currencies due to nationalism

The answer would be D.

Please mark me as brainliest.

Also hope this helps. 

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.

yes

it is because 3 because the citizen the northern democratic party watned the warning on red to blue because it is purple. lol