Why may it be hard for scientists to determine if a hominoid walked upright when discovering a skull?

a social contract.

"a social contract is an agreement between citizens and their leader where the citizens give up certain freedoms in exchange for protection. the constitution of the united states is an example of a social contract."

that would be the steamboat because none of the other things are forms of transportation

a reason that was key to coolidge's victory in the 1924 presidental election was that; democratic party supporters were split in the north and south.

multiple choice? can i see the answers?