A letter written by George Washington to his mother about the latest developments in the Revolutionary war. is it a primary or secondary source?

This would be a primary source.

Explanation:

Primary sources are first hand accounts. Since in this example, the letter is written by George Washington himself, it would be a primary source.

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for many centuries there were important factors which the economies of the muslim empires developed increasingly. they applied economic procedures in production, investment, finance, taxation and property. they used to tax certain goods (for example: harvest), they charged interest on money lent, they signed contracts with merchants; they relied on a common currency, and they used checks as well as promissory notes. with the money collected by means of taxation, the government provided the needy with an income. in addition, trading networks covered huge distances, so far regions started to have contact and exchange goods. this trade network covered areas of asia, africa and europe.