Final answer:
To prove the computations of the safety valve capacity, it can be done in four ways.
Step-by-step explanation:
The question is asking how to prove the computations of the safety valve capacity. The options provided are different ways to carry out the proof. In this case, the correct answer would be (c) four ways, as there are four possible methods to prove the computations of the safety valve capacity. It is important to note that without further information or context, it is not possible to provide specific examples of these four ways.