In parallelogram QRST shown below, diagonal is drawn, U and V are points on and , respectively, and intersects at W. If , , and , what is ? 1) 37º 2) 60º 3) 72º 4) 83º

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

Answer carbon dioxide ice;

Developed countries will see a decrease in natural resources, because their population will decrease.