There are gps satellites orbiting the earth.
a. 42
b. 10
c. 28
d. 24

There are 24, with 6 planes of orbit and 4 satellites in each. They are set up this way to be able to trace and triangulate any spot on the globe. There are also spare satellites for each plane that are at the ready to be launched when a main one goes down.

Ihave no idea what the answer is

So  if  the sum of the enthalpies of the reactants is greater than the products, the  reaction  will be  exothermic.  if  the products side has a larger enthalpy, the  reaction  is  endothermic. you may wonder why  endothermic reactions, which soak up energy or enthalpy from the environment, even happen