In an experiment, a control is used to establish a baseline to compare the results of the main experiment to. Having a control group rules out any environmental variables, such as temperature and... In an experiment, a control is used to establish a baseline to compare the results of the main experiment to. Having a control group rules out any environmental variables, such as temperature and...
Knives, including small pocket knives, are only allowed in checked bags. Only plastic and round-tip butter knives are allowed as carry-on blades. Most bladed items are allowed in checked baggage, including scissors, razors, swords, axes, box cutters and blade tools, if they are properly wrapped or sheathed.
This applies whether the flight is domestic within the US or international. Most flights that originate from outside the US have a weight limit for total checked baggage-a miserly 20kg/44lbs if you're traveling in coach class, 30kg/66lbs for business class and 40kg/88lbs for first class.