[单项选择]Cast iron and gunmetal fittings are used freely in small sizes at moderate pressure; large fittings, those for high pressure and temperature are cast or mild steelIn the above sentence, the word “those” means （）.
A. east iron firings
B. mild steel fittings
C. small fittings
D. large fittings

[单项选择]Cast iron pistons used in large propulsion diesel engines are constructed with （）
A. not taper what so ever
B. the skirt being tapered and smaller than the crown
C. the skirt being tapered and larger than the crown
D. the crown being tapered and smaller than the skirt

[单项选择]Many cast iron pistons are designed with heat dams, which serve to （）
A. keep piston crown temperatures elevated for smoother combustion
B. reduce the possibility of overheating the top compression ring
C. help retain the heat of compression to prevent ignition delay
D. help retain the heat of compression to prevent combustion knock

[单项选择]"Cast iron has poor corrosion resistance to sea water, especially in the presence of bronzes" Implies（）.
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 bronzes

[单项选择]The cast iron（）for the cross-head are attached to the top section and seal off the crankcase.
A. cylinder cover
B. cross-head shoes
C. guide-ways
D. scavenging boxes

[单项选择]（） of the A-frames there is a strong cast iron frame called the scavenging air box.
A. At the top
B. At the bottom
C. In the top
D. In the bottom

[单项选择]Cast iron carrier rings, （） machined grooves, are provided for all the pistons.
A. caulked into
B. caulking into
C. pressed into
D. screwed into

[单项选择]The cast iron guide-ways for （） are attached to the top section and seal off the crankcase.
A. the connecting rod
B. the cross-head
C. the piston rod
D. the air box

[判断题]WEP协议使用了CAST算法。

[单项选择]If a gasoline engine turns over freely but will not start，the cause is generally（）.
A. a defective ignition system
B. low lube oil level
C. weak valve springs
D. too heavy a load

[单项选择]If a diesel engine turned over freely but failed to start, the cause could be （）
A. water in the fuel
B. cold lube oil
C. excessive starting air pressure
D. excessive fuel pressure

[单项选择]The center of gravity of a freely swinging load suspended from a pedestal crane acts as if it were located at the（）.
A. counterweight
B. pedestal
C. longitudinal centerline
D. point of suspension

[单项选择]The fitting that allows a boom to move freely both vertically and laterally is called the （）.
A. swivel
B. lizard
C. spider band
D. gooseneck

[单项选择]Since heat will not flow freely from a body at a （） temperature to another at a （） temperature, it is necessary to expend mechanical work, heat, or electrical energy from an external source to achieve refrigeration.
A. lower；higher
B. shallower；deeper
C. larger；smaller
D. higher；lower

[单项选择]Large quantities of uncovered pig iron or billets should not be carried in the upper-tween decks because（）.
A. this does not eliminate the risk of cargo shifting
B. this will increase the metacentric height of the ship
C. this will decrease the gravity height of the ship
D. this will reduce the rolling period of the ship

[单项选择]Wrought iron has an inherent resistance to corrosion but is not to be had freely , its place has been taken by the cuprous alloysAccording to the above sentence , which of the following statements is true?（）
A. Wrought iron can resist liquids flow
B. It is difficult to attain the wrought iron
C. Wrought iron should be combined with cuprous alloys
D. The cuprous alloys have mere disadvantages than wrought iron

[多项选择]The Schuyler and Livingston Iron Works has been working on getting its network security under control. It has set up VPN with IPSec links to its suppliers. It has installed network vulnerability scanners to proactively identify areas of weakness, and it monitors and responds to security events as they occur. It also employs extensive access control lists, stateful firewall implementations, and dedicated firewall appliances. The company has been growing very fast lately and wants to make sure it is up to date on security measures.Which two areas of security would you advise the company to strengthen? （）
A. intrusion protection
B. identity
C. secure connectivity
D. security management

[单项选择]Cast irons weakness in tension and under shock loading limits its use to low pressure steam, air, oil and low speed water fittingsThe above sentence, most probably means （）.
A. cast iron has weakness
B. cast iron can stand up shock loading
C. cast iron fittings are only suitable in low pressure situation
D. east iron fittings are not suitable in low pressure situation

[单项选择]The iron mike is a(n) （）.
A. pilot
B. speaker
C. standby wheel
D. automatic pilot