The presence of armed guards usfrom doing anything disruptive（).

A . auto-ignition point B . flash point C . burning temperature D . fire point

A . center of gravity B . metacenter C . center of flotation D . keel

A . submerged hulls B . quarters C . columns and upper structure D . submerged connecting structure

A . promote refrigerant dehydration B . be absorbed in the receiver C . cause low condensing pressure D . carry moisture and lead to corrosio

A . boiling point B . flash point C . viscosity point D . toxic point

A . fuel valves of main engine B . injector pump of main engine C . safety valves of marine boiler D . safety valves of a reciprocating pum

A . heavy rain B . heavy snow C . thick fog D . clearing skie

A . as long as B . unless C . despite D . till

A . fuel oil vapor at the sludge tank vent B . unburned fuel vapors in the scavenge air receiver C . lube oil vapors in the crank case D . lube oil vapors in the engine room

A . flash point B . upper explosive limit C . lower explosive limit D . fire point

A . tightened up B . sealed up C . opened up D . unscrewed

A . flash point B . fire point C . upper explosive limit D . lower explosive limit

A . east iron is a cheap material B . cast iron can pollute sea water C . cast iron has mere corrosive than bronzes to sea water D . cast iron is more corrosive to sea water when it meets with bronze

A、onlooker B、catalysts C、master

A．was of his B．was of him C．did him D．did of his

A．To explain why some paints may deteriorate over the course of time B．To stress the need for caution when attempting to restore old artworks C．To show how pigments differ from varnishes and binding agents D．To show how spectroscopy can help establish the age of a painting 此题为多项选择题。

A:Increased capillary hydrostatic pressure due to congestion in operation; B:Increased capillary permeability due to vessel impairment in operation; C:Decreased plasma colloid osmotic pressure due to plasma loss in operation; D:Lymphatic obstruction due to removal of lymph nodes in operation; E:Increased tissue colloid osmotic pressure due to tissue damage in operation

Many researchers believe that the presence of RNA in brain cells is the biochemical basis of memory; that is, the presence of RNA enables us to remember. Because certain chemicals are known to inhibit the synthesis of RNA in the body, we can test this hypothesis. Animals that have learned particular responses can be injected with an RNA inhibitor and then tested for memory of the learned responses. Which of the following test results would most seriously weaken the case for RNA as the basis of memory？ A．After an injection of RNA inhibitor, a wide range of behaviors in addition to the learned responses were affected. B．After an injection of RNA inhibitor, animals that had not consistently been giving the learned responses were able to give them consistently. C．After injections of RNA inhibitor, some animals lost memory of the learned responses totally but others lost it only partially. D．After a small injection of RNA inhibitor, animals responded well, but as the size of the injection increased, they gave fewer of the learned responses. E．After an injection of RNA inhibitor, animals could not learn a new response.