If you set up an experiment with two different independent variables, then the results would

a. inconclusive; you would not know which of the two variables caused the change
b. definitive; the results would be more accurate if you change two variables at a time
c. conclusive; showing a strong correlation between dependent and independent variables
d. somewhat conclusive; you know the change resulted from one of the variables

An engineer designs a roller coaster so that a car travels horizontally for 152 ft, then climbs 137 ft at an angle of 34.0° above the horizontal. it then moves 137 ft at an angle of 48.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

In a good thermo flask the main cause of heat loss is

If two parallel light rays hit a mirror, they will not be parallel to each other after they reflect.