2 Answers

Weight = Mass * Acceleration
W = 45kg * 9.8 m/s2
W = 441 kg*m/s2 = 441N
According to the international system of unit (SI), kg*m/s2=N (Newton), therefore you have 441N.
Note: Weight is a force that pushes you in the direction of the acceleration of gravity, and since the unit of force is N, you have N also for Weight.

acceleration