First, we must know this:
Weight is a kind of force, P = m x g
m is the mass of the object and g is the acceleration of gravity
The unit of P in SI is N = kg m/(s)^2
Let's convert our mass in kg => 100,000 g = 100 kg
The acceleration of gravity = 9.8 m/(s)^2 (we assume this value)
Now, P = 100 kg x 9.8 m/(s)^2 = 980 N (newton)
Answer: 980 N