Final answer:
The persuasive claim in the message is "I'm sure you will be able to see the difference," which suggests confidence in the evidence to be provided during a proposed demonstration.
Step-by-step explanation:
The sentence in the message that identifies it as a persuasive claim is: "I'm sure you will be able to see the difference." This sentence serves as persuasive claim by asserting that a demonstration would clearly validate the issue being presented. It not only proposes an action but does so by instilling confidence that the problem is real and verifiable. It also implies that the demonstration will provide undeniable evidence to support the speaker's position about the speedometer's performance.
In the context of an analytical paragraph structure, this claim broadly aligns with point 2, as outlined in the instructional materials: making a specific claim that the paragraph argues is true, which in this case, is the effectiveness of a demonstration.