Is The reaction time is different for different stimuli
true or false?

true

Explanation: In this example, the processes (perceive, process, and respond), are done in a matter of milliseconds, but reaction time can vary depending on a variety of factors: Complexity of the stimulus-The more complex the stimulus, the more information that has to be processed, the longer this process will take.

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

give me abc and i will get it for u.