Is each statement true or false, why or why not?

11. Paulson leaves a desk in a private dump. A few days later, Paulson learns that the desk is a valuable piece of property. When Paulson returns to the dump, Carmine is placing the desk in his car. Paulson may obtain the desk. 12. Upon the death of a joint tenant, the remaining tenants take the share of the property. 13. Assurance must be made within 30 days after a written demand for adequate assurance. 14. One having absolute ownership of property may still find that the right to the property's use and enjoyment are subject to certain restrictions. 15. A writing is required for the sale of nonresellable goods with a price exceeding $500 when a substantial beginning has been made in the manufacture of those goods before the seller receives notice of the buyer's repudiation.