Why is the chemical formula magnesium sulfide written as mgs and not mg2s2?

Because you need only 1 atom of magnesium and 1 atom of sulfur to produce magnesium sulfate. Writing a two after each is not correct as that would be dimagnesium disulfide.

a person with a mass of 106kg has a weight of 1060n

  distance on the y-axis and time on the x-axis.

explanation:

the instantaneous velocity = change in position/time taken

the slope of the graph should give instantaneous velocity.

  slope of a graph = change in value of y -axis / change in values of x -axis

  comparing both the equations

    change in value of y -axis = change in position

  change in values of x -axis = time taken

so position values should be on the y axis and time values should be on the x axis.

distance on the y-axis and time on the x-axis.