Eduardo's mother just bought a new vacuum cleaner that she loves. eduardo wants to know if it really cleans better than the old one. he gets a few identical carpet samples and works an equal amount of sand and dirt into each one.
then he gets a panel of ten people to rate how well each vacuum cleans.

which of the following experimental setups will be the most objective and have the least bias?

a. eduardo leaves 1/3 of the samples dirty. he divides the other samples into two groups. he cleans each group with a different vacuum. he puts the samples in a random order, then asks the panelists to rate how clean each sample is.

b. the panelists watch eduardo use each vacuum to clean a carpet sample, then they rate how clean each sample is.

c. each panelist cleans one carpet sample with each vacuum, then rates how clean each sample is.

d. eduardo leaves 1/3 of the samples dirty. he divides the other samples into two groups. he cleans each group with a different vacuum, then he asks the panelists to rate how clean each group is.

Which religions are most commonly practiced in south asia

Ball is tossed up in the air at its peak, it stops before beginning to fall. the ball at its peak has

“dear sir: it is with great reluctance, i trouble you on a subject, which does not fall within your province; but it is a subject that occasions me more distress, than i have felt, since the commencement of the war; and which loudly demands the most zealous exertions of every person of weight and authority, who is interested in the success of our affairs. i mean the present dreadful situation of the army for want of provisions, and the miserable prospects before us, with respect to futurity. it is more alarming than you will probably conceive, for, to form a just idea, it were necessary to be on the spot. for some days past, there has been little less, than a famine in camp. a part of the army has been a week, without any kind of flesh, and the rest for three or four days. naked and starving as they are, we cannot enough admire the incomparable patience and fidelity of the soldiery, that they have not been ere this excited by their sufferings, to a general mutiny or dispersion. strong symptoms, however, discontent have appeared in particular instances; and nothing but the most acitive efforts every where can long avert so shocking a catastrophe.” what’s the central idea?