A 150 - 300 word response to the following question:

A market researcher is interested in knowing the type of training that works best for DVD users. Thirty consumers are randomly selected from a population of known DVD owners (i.e., users). Ten users are trained by giving them the DVD user's manual and allowing them to read it. Another ten users are trained from a 30 minute DVD user training video. Another ten users are trained from a self-paced computer tutorial. The users are then timed in their ability to setup and program the DVD by performing a series of operations. Which statistical analysis technique should be used? What is the null hypothesis? Can the market researcher get an answer? Why or why not?