Q3.) it's depends on you whether you are left or right handed, for me, I catch the ruler faster with my right hand.
Q4.) same as Q3
Q5.) for me, you can catch the ruler with your eyes open.
Q6.) the information moving along nerve pathways takes time because the information transmit to another neurons until it reaches the brain, the brain process the information and the response send to another neurons until it reaches the organs, glands or muscles.
Q7.) when body perceives a stimulus, the information quickly send to brain , when the brain process the information, it sends a response transmits to one neuron to another until it reaches your muscle in your hand and you would able to cathh it.