A) the works of ibn khaldun
b) the refinement of arabic numerals and the study of algebra
c) the study of eclipses and the calculation of earths circumference
d) the development of navigational devices such as the astrolabe and the sextant

in the declaration of independence, thomas jefferson announced that every human being has “certain unalienable rights,” among which are those to “life, liberty, and the pursuit of " hope i

donald carl johanson (born june 28, 1943) is an american paleoanthropologist. he is known for discovering – with yves coppens and maurice taieb – the fossil of a female hominin australopithecine known as "lucy" in the afar triangle region of hadar, ethiopia.

hope this !

i googled "who was kolson johanson" and this is the answer i found.

sorry if this is incorrect.

fairly positive it is 4

question as stated in comment

why did the chinese require the portuguese to pay for goods in gold and silver when trading?

choices

portuguese goods were less valuable than chinese goods.

the chinese already had a surplus of portuguese goods.

the imperial government wanted to stockpile gold and silver.

portuguese and chinese currencies were not exchangeable.

this a history q n in ancient time, theres no money exchange. so ans is portuguese and chinese currencies were not exchangeable.