Are these right and can u with number 4

Franklin neason earns $5,250 a month as a sales manager. what is his semimonthly salary? a.$10,500b.$5,250c.$2,365d.$2,625

Karen is financing $291,875 to purchase a house. she obtained a 15/5 balloon mortgage at 5.35%. what will her balloon payment be? a. $220,089.34 b. $219,112.46 c. $246,181.39 d. $230,834.98

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15