(i) Rate constant increases exponentially with increasing activation energy and decreasing temperature.

(ii) Rate constant decreases exponentially with increasing activation energy and decreasing temperature.

(iii) Rate constant increases exponentially with decreasing activation energy and decreasing temperature.

(iv) Rate constant increases exponentially with decreasing activation energy and increasing temperature

Correct Answer: (iv) Rate constant increases exponentially with decreasing activation energy and increasing temperature

Explanation: According to the Arrhenius equation, the rate constant increases exponentially with decreasing activation energy and increasing temperature.