Ascience class tested ways to clean water after an oil spill. each group of students was given 100 ml of vegetable oil, 100 ml of engine oil, and 800 ml of water in a rectangular plastic container. each container also held five floating wooden cubes (5 cubic centimeters each) representing animals in the water. each group was tasked with removing as much oil as possible in a 20 minute period, leaving “clean water” in the container, using whatever tools they brought to class. the results of the “clean-up” are presented in the table below. group vegetable oil removed (ml) engine oil removed (ml) 1 10 20 2 110 130 3 60 40 4 80 70 based on the results above, which group’s data seem unreliable?

According to the attached question, group 2's  data was not reliable because the sample given to each group was of 100 mL vegetable oil and 100 mL engine oil. But the results obtained by group 2 was more than the supplied amount of the oil which was 110 mL (vegetable oil) and 130 mL (engine oil).

Therefore, this was the group which obtained unreliable results.

pre-sliced bread is a relatively recent development in baking technology. previous to that, it was always sold in a bakery in daily-made contiguous loaves with no wrapping, and was moderately perishable, usually being used with a day or two (which is why every bakery had a discounted “day-old” bread table.) therefore, pre-sliced bread would grow stale quickly. the hard crust provided a protective layer, and once the exposed dry slice left from the previous cut was removed, the interior was still soft.

what keeps bread soft is the moisture retained in the crumb (the light spongy part that’s not crust). the reason the crust develops is the surface of the dough gets exposed to hot dry air during baking which browns the outer layer and seals it, preventing all the moisture from escaping the dough. longer exposure to air will also eventually cause your bread to lose flavor and become stale.

people were used to cutting slices as they needed them and storing bread in a specially-made wooden or metal breadbox or pail with a lid to preserve it longer, but the first automatically sliced commercial loaves were produced on july 6, 1928, in chillicothe, missouri, using a machine invented by otto rohwedder, an iowa-born, missouri-based jeweler.[1] pre-sliced bread would indeed dry out, were it not for another 20th century technology: the plastic bag. bread could now be pre-sliced, and if the enclosing bag remains sealed as much as possible, the bread will remain soft and fresh for longer than if sitting unwrapped on a shelf or enclosed in a bread box that is not air-tight. sealed packaging meant bread could also be sold on store shelves and eliminate frequent trips to a bakery.

sealing bread in a plastic bag had another effect: the moisture in the loaf will re-distribute into the crust and soften it, which is sometimes more pleasing in a sandwich - especially for children whose teeth might not yet be strong enough to tear through a hard crust. a homemade loaf of bread can be sealed in a bag overnight and the crust will become soft like store-bought sandwich bread.

these were novel changes in how bread was produced and sold, which led to the coining of the phrase “the greatest thing since sliced bread.”

your answer would be “dry”