Answer:
What is the mass of 3 kg?
So, to answer your question, weight=mass*gravity, so 3kg*9.8m/s^2=29.4 kgm/s^2. Kilogram meters per second squared is the unit for force also known as Newtons (N). So, your book has a weight of 30 N. Weight is a function of mass (M) and gravity (g).