F the simple interest on $4000 for 6 years is $1440, then what is the interest rate?

Just tell me how to set up the equation.

Last week , donnell practiced the piano 3 hours longer than marcus . together, marcus and donnell practiced the piano 11 hours . for how many hours did each young man practiced the piano

For a school science project, john noted the temperature at the same time every day for one week. the high temperature for the week was 27°f, and the low temperature for the week was −3°f. what is the difference between the high and low temperatures john recorded?