Ascientist wants to know if adults prefer watching movies in a theater or in their home. he interviews 500 people leaving a local movie theater and finds that 480 of them like watching movies in theaters. the scientist concludes that 96 percent of people like watching movies in theaters more than at home. why is the scientist's conclusion most likely unreliable? not enough people were interviewed. the investigation was based on preferences. the investigation was not replicable. the location of the survey introduced bias.

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.