Superior Sales Corporation (Superior) mailed a copy of an employment contract to Mariano offering the latter the position of manager of the company's branch office in Legaspi City. The contract provided for a monthly salary P80,000. Mariano accepted the offer by signing on the space for "Conforme". However, he wrote a marginal note asking the company to grant him a housing allowance of P20,000 since he would be relocating from Manila. He then mailed back the signed copy of the contract. Was there a perfected contract between Superior and Mariano?