Question

type scissor jack with the spare tire. these jacks are light weight and inexpensive to produce, but have limited load capacity. therefore, never lift a heavy vehicle with a jack from a lighter vehicle.

• bottle jacks use hydraulic forces to operate. they usually have greater lift capacity than most scissor jacks. most heavy vehicles include a bottle jack with the spare tire as standard equipment.

floor jacks are hydraulically operated and are commonly found in automotive repair shops. they offer improved accessibility to vehicle lifting points and require less effort to operate. they are usually more expensive and less portable than a scissor or bottle jack.
warning! never position your body under a vehicle supported only by a jack. if the jack fails, you could be easily crushed.
always support the weight of the vehicle with jack stands rated to support the vehicle weight and test to ensure the vehicle is safely supported by gently rocking it before going under the vehicle.
never use \home made\ jack stands or support the weight of the vehicle with only wood or concrete blocks that could split or crumble.
using the right jack for the job is always best to accomplish lifting.
which of the following are safe practices?
never use a scissor jack from one car to lift another car of different make and model.
wood or concrete blocks are suitable alternatives to jack stands.
always support the weight of a vehicle with properly rated jack stands.
\home made\ jack stands are safe to use as long as they appear sturdy.

Explanation:

The text warns against using a scissor - jack from a lighter vehicle to lift a heavy one, and against using wood or concrete blocks, and "home - made" jack stands for vehicle support. It emphasizes always using properly rated jack stands. The first option about not using a scissor jack from one car to lift another is not a general safety practice mentioned in the text. The second option is incorrect as wood or concrete blocks are not suitable. The fourth option is wrong as "home - made" jack stands are not safe. The third option about using properly rated jack stands is a safe practice.

Answer:

Always support the weight of a vehicle with properly rated jack stands.