Answer:
3531 joules of Potential energy
Step-by-step explanation:
2 floors 3.0m floor apart means that she climbed 6 total meters upwards, if that is the case then you use
U=mgh where U is potential energy, m is mass, g is gravity(9.81 m/s^2 on earth, you can assume it's this basically every time) and h is 6 meters. If she climbed some other height just replace the h with it instead of 6.