What is the dependent variable when collecting data using the emg sensor?

Aletter or menu command that starts an action when the user presses the designated letter and the alt key together is called what?

I'm taking a class on how to make a movie, and it offers some apps that would be in the process. the thing is, i don't have any of those ha. if you have any tips on some apps i could use, that would be awesome. i don't have an iphone, so don't suggest any apps like imovie. i know that this is a weird question, but it would be super for me. : )

When you mouse over and click to add a search term this(these) boolean operator(s) is(are) not implied. (select all that apply)?