Final answer:
The tonnage per piston of an acme machine depends on the machine's specific model and design specifications. Without additional context or information, it's impossible to determine the correct answer to the question.
Step-by-step explanation:
The question regarding how many tons per piston an acme machine has cannot be accurately answered without additional information about the specific model of the machine in question. Typically, industrial machines like presses or hydraulic systems have varying capacities, which are defined by their design specifications. If you're referencing a manual, technical specifications sheet, or product description, it would state the tonnage capacity of each piston.
If the acme machine in question is part of a hypothetical scenario or textbook problem, the correct answer should be found in the associated text or materials provided in your course. It's important to review the context in which the question was asked to determine the correct tonnage per piston. If this information is not available, then it is not possible to provide a definitive answer to the question.