On September 1, Debtor (D) requested a loan from Secured Party (SP). After examining D's financial condition, SP agreed to make the loan. D signed a security agreement on September 3 covering certain described collateral of D. On that date, SP initiated a search of the records in the state filing office, and, when it discovered that no other financing statements were on record, filed its financing statement on September 5 and advanced the requested funds to D on September 6. When did SP's security interest attach? When was SP's security interest perfected? See 9-308(a), 9-502(d). Assume that D purchased an asset on September 6 covered by the collateral description in SP's filed financing statement. When was SP's security interest in it perfected