10 -Seja a média aritmética de três números (x, y e z), e seja a média aritmética ponderada desses números relativa aos pesos 2, 3 e 5, respectivamente. Considere as afirmativas abaixo relativas às médias e .
I.Se x = y = z, então = .
II.Se x = 1, y = 2 e z = 3, então > .
III.Se z = x + y, então > .
IV.Se = , então 5z = 4x + y.
Assinale a alternativa correta:
a)Somente as afirmativas I e II são verdadeiras.
b)Somente as afirmativas II e III são verdadeiras.
*c)Somente as afirmativas I e IV são verdadeiras.
d)Somente as afirmativas II, III e IV são verdadeiras.
e)Somente as afirmativas I, III e IV são verdadeiras.
Food Preserving Processes
There are different ways of preserving food. The first way that our ancestors found out about, long ago, was to cook the food. The cooking killed off the microbes that were already in it. Then, our ancestors found out about drying food. Dried food kept for a long time because microbes need water to grow. Later on, cold was found out to be a very useful way of keeping food fresh. Nowadays, different processes of preservation include canning, pickling in vinegar or brine (salt water), cooling, freezing. These processes have made it possible to keep food fresh for weeks, months, and even years.
11 -According to the text:
a)The need to preserve food is recent.
b)Our ancestors did not know how to preserve food.
c)Cooking is not a food preserving process.
*d)Food can be pickled in vinegar or in salt water.
e)Microbes are present in dried food.
12 -According to the text:
a)Nowadays many people like pickled food.
*b)Freezing food is one way of keeping food fresh for years.
c)Our ancestors did not like frozen food.
d)Drying is not used for preserving food nowadays.
e)Cooking was the second way our ancestors found out to preserve food.
13 -Which of the following lists of food preserving processes are mentioned in the text?
I.Freezing, canning, cooling, and pasteurizing.
II.Cooking, pickling, drying, and cooling.
III.Canning, smoking, freezing, and drying.
IV.Drying, canning, freezing, and pickling.
a)Only the processes in I and II are mentioned in the text.
b)Only the processes in II and III are mentioned in the text.
c)Only the processes in III and IV are mentioned in the text.
d)Only the processes in I and III are mentioned in the text.
*e)Only the processes in II and IV are mentioned in the text.
14 -What information is in the text?
a)Louis Pasteur found out that heating killed off microbes.
*b)Freezing keeps food from going bad.
c)Fruits and vegetables are cooled at different temperatures.
d)There are many kinds of foods that need to be kept in a refrigerator.
e)Antioxidants are used for food preserving.
15 -In the sentence: "The cooking killed off the microbes that were already in ", the underlined pronoun refers to: