A student performs an experiment to see how catalysts affect the rate of a reaction. He notices that when the reaction is nearly finished, it stops bubbling. He wants to know how much faster the reaction occurs when a catalyst is used. Which is the best method for him to measure his data? Use a stopwatch to record the time it takes for the bubbling to stop. Estimate the time of the reaction by counting aloud. Count the number of bubbles formed by the reaction. Measure the size of the bubbles produced with a ruler.