Electronic configuration of ABCD which is most metallic ​

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

Given that 1 mi = 1760 yd, determine what conver- sion factor is appropriate to convert 1849 yd to miles; to convert 2.781 mi to yards.

Identify the lewis base in this balanced equation: fe3+ h2o fe(h2o)63+