Objective 5

1.  Boyle's law describes the relationship between the absolute pressure and the volume of a gas
http://en.wikipedia.org/wiki/Boyle's_law

2.  Because high-altitude balloons displace a greater weight than itself so it could blow up or not be able to fly if it wasn't half filled
http://www.google.com/search?hl=en&rlz=1R2SUNA_enUS327&q=why+do+scientists+only+half+fill+high+air+balloons%5C&aq=f&aqi=&aql=f&oq=&gs_rfai

3.  The equation for Boyle's law is PV = k or you could say P₁V₁=P₂V_2.
P= the pressure
V= the volume of the gas.
K= the value representative of the pressure and volume
http://en.wikipedia.org/wiki/Boyle's_law

4.  It could  help with how much pressure you should press on somebodys volume???? I was completely confused on this one

5.  Boyle's law gives simple rules to Scuba diving, for example consider the pressure of the water, so how far down can you go, the volume of your body....etc
http://scuba-doc.com/surgdiv.html