What must be known for the rate constant to be calculated from the rate law? A. The temperature at the beginning if the reaction
B. The reaction rate at known product concentrations
C. The reaction rate at known reaction concentrations
D. The activation energy the reaction must overcome

C. The reaction rate at known reaction concentrations

Explanation:

The rate of a reaction is the measure of the speed of a chemical reaction. To find the rate constant of a reaction, the concentration of the reactants must be known.

while cooking a piece of 1/2 pound beef steak, a cast iron pan (2.4kg in weight) was heated 260 celsius.

i think that the answer is c