At a certain excavation site, archaeological studies have used the method of tree-ring dating in an effort to determine when people lived in there. wood from several excavations gave a mean of (year) 619 with a standard deviation of 42 years. the distribution of dates was more or less mound-shaped and symmetrical about the mean. use the empirical rule to estimate a range of years centered about the mean in which about 99.7% of the data (tree-ring dates) will be found.

a function could be identified in 3 ways either on a chart,graph, or ordered pairs. first a function is that each point has its own. the rule is that there can be many x's to one y but there can not be 2 x's at different y's. so on a graph when you put a straight line through the y's there should be one dot only to be a function.

step-by-step explanation:

it is contrapositive

i could not see the question too well so check yourself again too . this is because i want you to get it correct.