The mass of a block is 8g and the volume is 4ml.
a) calculate the density of the block. show your work.
b) will it sink or float in water?
c) is this block more likely made of styrofoam or more likely made of metal?
d) why?
(i am getting this some, i just mostly do not quite get how i'll know if the object will either float or sink.)

To place a communications satellite into a geosynchronous orbit at an altitude of 22,240 mi above the surface of the earth, the satellite first is released from a space shuttle , which is in a circular orbit at an altitude of 185 mi, and then is propelled by an upper-stage booster to its final altitude. as the satellite passes through a, the booster's motor is fired to insert the satellite into an elliptic transfer orbit. the booster is again fired at b to insert the satellite into a geosynchronous orbit. knowing that the second firing increases the speed of the satellite by 4810ft/s, determine (a.) the speed of the satellite as it approaches b on the elliptic transfer orbit, (b.) the increase in speed resulting from the first firing at a.