Johns Hopkins University tricked a Montgomery County farm owner into helping the university establish an office park on land she donated, violating their agreement, the donor’s family told a Maryland Circuit Court judge Wednesday. But attorneys for the university said Hopkins’ plans for the 108-acre former farm comply with the agreement struck when Elizabeth Banks sold the land to the university for $5 million. The university asked the judge to dismiss the case, while Banks’ relatives want the issue decided in a civil trial.