The International Space Station (ISS)

Part 1 - (a) How big is the ISS, (b) what is the altitude that it orbits at, (c) how long does it take to orbit the earth, and (d) how many occupants are typically on it at any one time?

The ISS has a volume as large as a Boeing 747 (over 30,000 ft³) ... if you include the solar arrays, it spans the area of 8 basketball courts.
It orbits anywhere between 205 and 270 miles above the surface of the earth.
The ISS orbits the earth 15½ times every day  .... taking just 92 minutes to complete one orbit.  FYI, it travels slightly over 17,000 mph.
A full crew is considered six occupants but that number varies over time.  There have been up to ten occupants and as few as three persons at a given time.  The crew rotates but astronauts like Peggy Whitson and Scott Kelly have spent a lot of time in space.

Part 2 - Research the details of one project or study performed on the ISS.  Please list the experiment as well as the results of that experiment.

The answers may vary.

Part 3 - In the movie Gravity, you saw one potential danger for persons orbiting in space - being hit by debris ... either man made or natural meteors.  How serious is this threat or was this just Hollywood hype?  Please give specific data and/or work done on this subject. 

Space debris is a very real threat to the safety of the crew.  Obviously, the bigger the object, the bigger the threat.  The hull of the ISS has a protective film over it to absorb the energy of an incoming object.  In addition, space debris is tracked from ground radar and the ISS has had to make several maneuvers in the past to avoid it.  In case of a problem, they close all hatches and retreat to a Soyuz spacecraft.

Part 4 - Besides the obvious dangers of launch and reentry (as well as the potential danger listed in part 3), what are some other life threatening obstacles that could pose danger to occupants of the ISS?  What is being done to minimize the risks?

The answers may vary.    It was well known that long term exposure to zero-g environment can cause atrophy to muscles and bone density.  That is why exercise and diet is strictly monitored.  However, in a long term study, it was discovered that occupants of the ISS experience vision problems over long periods of time ... likely cause by too much blood flowing to the head.  This could cause a potential risk to future missions to Mars.  The solution was to reduce the blood flow to the head by having occupants wear vacuum pants (so more blood would flow to the lower extremities ... like it does at the surface of the earth).

Part 5 - The ISS often makes visible passes over your location.  When is the next visible pass for you?  Note: there are several web sites and smart phone apps that supply this information.  Why do you think the best time to see the ISS is just before dawn or just after dusk? 

Remember, the ISS only reflects sunlight so the craft still needs to be in the line-of-site of the sun.  You need a dark sky to observe the ISS but the craft itself must still be in sunlight.  This only occurs before dawn or after dusk.