Why does mass not affect the period of a pendulum?

Time period can be written as 2π √L/g so it doesn't depend on mass !

As the mass increases so will the force on the pendulum.

There is no graph to look at on here, but i shall explain them to you. a line graph is just in its title it’s a graph with a line running through the dots to show an increase or decrease. a bar graph is used to show how much or how little something is so a comparison. a scatter plot is used to graph points to tell the data. and i don’t know what a histogram is.