PLEASE PLEASE HELP ME I have a few questions that i dont know how to anser

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The discussion revolves around a user seeking help with six specific science questions related to physics and thermodynamics. Key topics include the buoyancy of ice in water, the relationship between heat added and work done in a system, and the effects of temperature changes on different materials. Participants emphasize the importance of showing work for problem-solving, as per forum rules. The user is encouraged to clarify their understanding of the concepts involved to receive more effective assistance. Engaging with the community can lead to better comprehension of these scientific principles.
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PLEASE PLEASE HELP ME! I have a few questions that i don't know how to anser!

I have six questions here that I have no idea how to anser. If anybody can help me and explain them to me, I'd really really really appreciate it. Thanks alot

When ice floasts in water, a small part of it extends above the surface. Interestingly enough, the volume of ice that extends above the surface is equal to the volume of the...
a. vast number of open spaces in the hexagonal ice crystals
b. water the ice displaces
c. both of these
d. neither of these

2.When 100 J of heat is added to a system that performs 60 J of work, the thermal energy change of the system is...
a. 0j
b. 100j
c. 60j
d. 40j
e none of these

3. When work is done by a system and no heat added to it, the temperautre of the system...
a.increases
b. decreases
c. remains unchanged

4. A container of air is at atmospheric pressure and 27 degrees c. to double the pressure in the container, it should be heated to...

5. A piece of iron and a cup of waterboth have the same temperature. if they are heated so the thermal energy of each doubles,...
a.the water will have the higher temp.
b. the iron will have the higher temp
c. both will have the same temp.
d. not enough information

6. Which of the following contracts most when the temp. is decreases? equal volumes of
a. iron
b. wood
c. helium
d. water
e. none of the above
 
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