In a closed system one kilogram of carbon dioxide (CO_2) is expanded reversibly from 30 degree C and 200 kPa to 100 kPa pressure. If the expansion is polytropic with n = 1.27, determine the total work, the change in total internal energy, and the total heat transferred in [kJ], Note that for CO_2, R = 188.9 J/kg. K and c_v = 655 J/kg. K. W = -29.05 kJ, DeltaU = -27.19 kJ, Q = 1.860 kJ

When selecting a savings account, you should look at the following factors except annual percentage yield (apy) fees minimum balance interest thresholds taxes paid on the interest variable interest rates

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.

Which of the following is the term for something that you can't live without 1. need 2. want 3. good 4. service