Having some trouble. Please help!?

Question

Levers are classified according to the positions of the effort, the fulcrum, and the resistance. Which one is in between in a) a first-class lever, b) a second-class lever, and c) a third-class lever?

and

Describe three valuable uses of radioactive isotopes. Provide an example of each.

Answer 1

1st LFE

2nd FLE

3rd FEL

where:

L=load

F=fulcrum

E=effort

click the sites below to know the uses of isotopes:

http://www.chem.duke.edu/~jds/cruise_che...

http://www.radiochemistry.org/nuclearmed...

Answer 2

I always remember F-L-E = 1-2-3 lyrically and the one in the center determines order.

ie. L -- F -- E is first order, F -- L -- E is second and F -- E -- L is third.

wikipedia can help you with the last question. Briefly, Americium-231 is used in smoke detectors, Technicium-99m is used in medical diagnosis, Cobalt-60 is used in medical treatment to name three.