Two groups of students were tested to compare
their speed working
math problems. Eac
group was given the
same problems. One
group used calculators
and the other group
computed without
calculators

Oh dog

The one that would be the most effective means of controlling current water pollution of us surface water is : shutting down factories that discharge materials to the rivers.the largest sum of us pollution currently caused by factory-related substance

Na+ loss through sweet plus the dilution has lowered na+ concentration outside of neurons, altering the na+ equilibrium potential. sodium exists more outside the cells than inside. when na+ is lost by sweat plus the dilution( because they drink a lot of water) changes the concentration outside the cell, forcing the water to enter the cell and attempt to balance the concentration inside/outside.the problem is that the abundance of water will cause the cells to swell. most cells can adapt, however, the brain cells can't that's why the runner has confusion and can't control the muscles.  if not treated and this occurs in less than 48 hours, it can be immediately fatal .

Any choices to answer !