Why is it important to know there are good and bad bacteria?

What was a major failing of the united states under the articles of confederation?

Which is true of the kentucky and virginia resolutions? they called for more influence from the federal level. they reinforced the ideas behind the alien and sedition acts. they were written by thomas jefferson and james madison they gave congress final say over what was deemed constitutional.

The picture below shows president richard nixon and the first lady standing before the great wall of china in 1972. they are smiling - as are the chinese with them. when this picture was shown on american television, americans were aware that it was a historic moment. what are two reasons why this moment was important for both china and the united states?