A process stream of dilute aqueous solution flowing at the rate of10 Kg.s-1 is to be heated. Steam condensate at 95°C is available for heating purpose, also at a rate of 10 Kg.s-1. A 1 - 1 shell and tube heat exchanger is available. The best arrangement is

• counter flow with process stream on shell side.
• counter flow with process stream on tube side.
• parallel flow with process stream on shell side.
• parallel flow with process stream on tube side.