Discuss the most important development in the various periods of the ancient Egyptian civilization

Egypt was developing day by day with improved education, maths and astronomy. They also invented a wide range of things.

the answer to your question is a. the salt plains

in 1811, he led an expedition, known as the george c. sibley expedition, to improve relations with the pawnee and kansa tribes, and also to locate the rumored jefferson's salt mountain

answer

the statement that best describes president carter’s attempt to free the hostages in iran is c. all of the attempts failed.

explanation

the operation eagle claw conducted by the united states armed forces was a failed mission which aimed to rescue 52 americans captured as hostages in the american embassy, tehran on 24/4/1980.the mission was authorized by president jimmy carter. the failures included;   obstacles in operation that included operational conditions challenges caused by sandstorms, hydraulic problems of one the helicopters and , mechanical failure of another helicopter that was identified as a cracked rotor blade and the crashing of another helicopter during mission abortion causing death of 8 service persons.