Atest consists of 20 problems and students are told to answer any 10 of these questions. in how many different ways can they choose the 10 questions?

You are making a battery for a science project. you have copper wire for your first electrode. you need to choose a conductor, a second electrode, and a device to plug into your battery. you have already chosen a lemon conductor. complete each statement below about the options that include a lemon conductor.