716 decimeters + 840 centimeters = meters?

80 meters

1 m = 10 dm

716 dm = 716 : 0,1 m = 71, 6 m

1 m = 100 cm

840 cm = 840 : 0,01 m = 8, 4 m

716 dm + 840 cm =

= 71,6 m + 8,4 m

= 80 meters

think its the third option

probably not the "magnets"in the magnet, so to speak, are thought to be electrons orbiting in shells. vurrent loops two sides to the loop