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”
The answer is high pressure. In a nuclear reaction process, high temperature and high pressure is required for turning hydrogen nuclei into a helium nucleus. It is impossible for it to happen simultaneously because it requires tremendous amounts of energy. Extreme conditions are required for the atoms to overcome electrostatic repulsion.
I belive the answer to the first one is no I would have to assume a habitual zone is one area on a planet. for example, an air conditioned building vs. the Savvanah dessert. However I am not sure maybe other answers will help more on this one. Sorry.... Earth-like planet would of course need water, plant life, animals, oxygen, fossil fuels etc. A challenge we would face on a travel to another liveable planet: do we have engough transportation? engough fuel to make it? How long can we live on this planet? Who or what else is present here? etc. Yes I do think they should discover a planet with earth like qualities befor investing in tools to get us to them. So money is not wasted. (make sure to put this into your own words )