单项选择题

The water jar mentioned in the second paragraph can NOT be described as ______.

A．light in weight
B．made by a Native American
C．an example of fine art
D．an object to be used

<上一题目录下一题>

热门试题

单项选择题The author focuses primarily on ______.

A．two competing scientific models concerning the sun's magnetic field
B．an overview of some recent scientific developments in solar physics
C．the reasons why a problem in solar physics has not yet been solved
D．the difficulties involved in linking terrestrial climate with solar activity

单项选择题On which of the following assumptions is based the belief, that tree-ring thicknesses show links between solar periodicity and terrestrial climate

A．Solar-activity cycle existed m its present form during the period in question.
B．Average tree-ring thickness varies from species to species.
C．Tree-ring thickness varies with changes in terrestrial climate.
D．Both terrestrial climate and solar-activity cycle randomly affect tree-ring thickness.