Both the olmec and mayans carved glyphs into stone objects. what does this suggest about both civilizations?

the  seven  days  battles  were  a series of seven battles over seven  days from june 25 to july 1, 1862, near richmond, virginia,  during  the american civil war. the  seven  days ended with mcclellan's army in relative safety next to the james river, having suffered almost 16,000 casualtiesduring  the retreat.

this is a good question! i'll do some research and come back when i have the answer!