What is the formula to find average speed?

In a given chemical reaction, the energy of the products is greater than the energy of the reactants. which statement is true for this reaction?

Carbon is allowed to diffuse through a steel plate 15 mm thick. the concentrations of carbon at the two faces are 0.65 and 0.30 kg c/m^3 fe, which are maintained constant. if the preexponential and activation energy are 6.2 x 10-7 m2 /s and 80,000 j/mol, respectively, compute the temperature at which the diffusion flux is 1.43 x 10^-9 kg/m^2 -s.

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c