1) All materials have the same properties. a) True  b) False 2) A problem is a thing or situation that needs to be solved. a) True b) False 3) 4. An engineer’s goal is to find the best solution to a problem a) True b) False 4) 5.Engineers build their product based on the first idea they have. a) True b) False 5) 1.Tools help us … a) a) do a specific job. b) b) make an effort. c) c) work more. d) d) make things more difficult. 6) Machines help us to a) a) identify a problem. b) b) reduce the effort we need to do things. c) do a specific job d) make an effort 7) A example of light materials is a) a)wood b) b)glass c) c) leather. d) d)paper. 8) A example of hard materials is a) a)wood b) b)fleece c) c) zipper d) d)paper. 9) A example of soft material is a) a)glass b) b)fleece c) c) zipper d) d)paper. 10) 6. When two or more simple machines are used together, they make a … a) a)complex machine b) b)valve c) c)tool d) d)simple machine 11) 7.The point where a lever rests is the … a) a) beam b) b)fulcrum c) c)pivot d) d) pulley 12) A lever and a pulley are used to… a) a) cut through hard objects. b) b) design a machine. c) c) lift heavy objects. d) d) make a hole in a material 13) The ramp of a school is .... a) a) inclined plane b) b)lever c) c)pulley d) d)screw 14) A wedge is used to a) a) design a machine. b) b) move objects. c) c) lift heavy objects. d) d) cut through hard objects. 15) A valve a) a) makes our lives better and easier. b) b) helps move something. c) c)controls the flow of a liquid or gas. d) d)can measure how long something is. 16) A check valve a) a)only allows liquids or gases to move in one direction. b) b) is never used in machines. c) c) cuts through hard objects. d) c) allows liquids go in one way and out another. 17) Is this a simple or complex machine? a) simple b) complex 18) Is this a simple or complex machine? a) simple b) complex

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