mass balance n heat balance 1

mass balance and heat balance...

i try to post this into my blog, cause i think, my work is wrong...because i found (-) in my answer...

Liquid as much as 5 m³ in stirred tank vessel is heated in batch operation. The vessel is equipped with heating coil: heat transfer area 3 m² and overall heat transfer coefficient U_D = 4200 cal/(m².hr.°C). Liquid density is 0.95 g/cc and its specific heat is 0.3 cal/(g.°C). The initial temperature of liquid in the stirred tank is 30°C, and the target temperature is 110°C. Steam is used as heating médium, which condenses in the coil at 150°C (constant). Due to poor pipe fitting and connection in the outlet stream, there is leak flow from the effluent stream, around 0.3 m³/hr. The volume of liquid in the tank is maintained by feeding the fresh liquid into the tank, at the flowrate of 0.3 m³/hr and 30°C. How long is the target temperature reached?

can you help me???anyone???