42. When Business Week published “The Portable Executive”, it implied that .
A. systems for managing telecommuters were not effective.
B. there was resistance on the part of many managers about telecommuting.
C. the trend for telecommuting was optimistic.
D. most telecommuters were satisfied with their work.
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct
answer to each of the questions.
The mineral particles found in soil range in size from microscopic clay particles to large boulders. The
most abundant particles - sand, silt, and clay - are the focus of examination in studies of soil texture. Texture
is the term used to describe the line composite sizes of particles in a soil sample, typically several
representative handfuls. To measure soil texture, the sand, silt, and clay particles are sorted out by size and
weight. The weights of each size are then expressed as a percentage of the sample weight.
In the field, soil texture can be estimated by extracting a handful of sod and squeezing the damp soil into
three basic shapes; cast, a lump formed by squeezing a sample in a clenched fist; thread, a pencil shape
formed by rolling soil between the palms; and ribbon, a flatfish shape formed by squeezing a small sample
between the thumb and index finger. The behavioral characteristics of the soil when molded into each of
these shapes, if they can be formed at all, provides the basis for a general textural classification. The
behavior of the soil in the hand test is determined by the amount of clay in the sample. Clay particles are
highly cohesive, and when dampened, behave as a plastic. Therefore the higher the clay content in a sample,
the more refined and durable the shapes into which it can be molded.
Another method of determining soil texture involves the use of devices called sediment sieves, screens
built with a specified mesh size. When the soil is filtered through a group of sieves, each with a different
mesh size, the particles become grouped in corresponding size categories. Each category can be weighed to
make a textural determination. Although sieves work well for silt, sand, and larger particles, they are not
appropriate for clay particles. Clay is far too small to sieve accurately; therefore, in soils with a high
proportion of clay, the fine particles are measured on the basis of their settling velocity when suspended in
water. Since clays settle so slowly, they are easily segregated from sand and silt. The water can be drawn off
and evaporated, leaving a residue of clay, which can be weighed.
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