A researcher wants to know if the same parenting style used effectively on urban children at a young age will remain as effective as the same children get older. The researcher would most likely conduct the research using which descriptive research method?
A.
naturalistic observation
B.
longitudinal study
C.
cross-sectional study
D.
case study

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

How does an observation about an object differ from an inference about that object

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)