Explanation:(a) Was this an observational study or an experiment? Explain your reasoning. Experiment, because certain variables were controlled (he sets the screen brightness to low and then starts a movie) to determine if iPhones last longer if the screen brightness is set to low, and it proves the cause and effect relationship.
(b) What is the explanatory variable and the response variable? Response Variable- To determine if iPhones last longer if the screen brightness is set to low Explanatory variable- he sets the screen brightness of 10 of the iPhones to high and starts a movie, then the other 10 to low and starts a movie.
(c) Was a random sample used to collect the data? Yes- “he selects a random sample of 20 brand new iPhones”
Scarcity-fundamental economic problem facing all societies that results from a combination of scarce resources and people's virtually unlimited wants
It's A) Encourage lots of little behaviors to add up into one large action.
Hope this helps, Good luck! (:
Answer:
C. interact frequently with the audience.
Explanation:
Presentation can be defined as an act of talking or speaking formally to an audience in order to explain an idea, piece of work, project, and product with the aid of multimedia resources or samples.
Students who want to create an effective presentation should interact frequently with the audience.
This ultimately implies that, to create an effective presentation, speakers are saddled with the responsibility of interacting more often with the audience by taking questions, making a joke, getting them to repeat informations loud at intervals etc.
Additionally, students are advised to be passionate and show enthusiasm during their presentation because it would enhance their ability to speak confidently and as such leading to an engaging presentation.
