Final Answer:
The force needed to lift the 20-kg crate is C. 204 N.
Step-by-step explanation:
In physics, the force required to lift an object can be calculated using the formula: Force = mass × acceleration due to gravity.
The acceleration due to gravity on Earth is approximately 9.8 m/s².
For the given 20-kg crate, the force needed is:
[ \text{Force} = 20 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 196 \, \text{N}.\]
However, it's crucial to consider that the crate experiences the force not only due to gravity but also due to the worker's effort to lift it.
This additional force is often equal to the weight of the object.
Therefore, the correct force needed to lift the crate is 196 N + 8 N (approximately) = 204 N.
In summary, option C (204 N) is the correct answer as it accounts for both the gravitational force and the additional force required by the worker to lift the crate.