The slope of a demand curve is not used to measure the price elasticity of demand because
a) the slope of a linear demand curve is not constant.
b) the slope of a line cannot have a negative value.
c) the measurement of slope is sensitive to the units chosen for price and quantity.
d) the slope of the demand curve does not tell us how much quantity changes as price changes.

How did the contribution of the goods producing sector to gdp growth change between 2010 and 2011 a. it fell by 0.3%. b. it fell by 2.3%. c. it rose by 2.3%. d. it rose by 0.6%. the answer is b

Reliability and validity reliability and validity are two important considerations that must be made with any type of data collection. reliability refers to the ability to consistently produce a given result. in the context of psychological research, this would mean that any instruments or tools used to collect data do so in consistent, reproducible ways. unfortunately, being consistent in measurement does not necessarily mean that you have measured something correctly. to illustrate this concept, consider a kitchen scale that would be used to measure the weight of cereal that you eat in the morning. if the scale is not properly calibrated, it may consistently under- or overestimate the amount of cereal that’s being measured. while the scale is highly reliable in producing consistent results (e. g., the same amount of cereal poured onto the scale produces the same reading each time), those results are incorrect. this is where validity comes into play. validity refers to the extent to which a given instrument or tool accurately measures what it’s supposed to measure. while any valid measure is by necessity reliable, the reverse is not necessarily true. researchers strive to use instruments that are both highly reliable and valid.

Match each economic concept with the scenarios that illustrates it