AB+C follows an elementary rate law and is to be carried out first in a PFR and then in a separate experiment in a CSTR. When pure A is fed to a 10dm3 PFR at 300K and a volumetric flow rate of 5dm3/s, the conversion is 80% When a mixture of 50%A and 50% inert (I) is fed to a 10dm3CSTR at 320K and a volumetric flow rate of 5dm3/s, the conversion is also 80%. What is the activation energy in cal/mol