El Nino occurs every 2 to 12 years

the correct answer is true

These are resources that cannot be renewed after used. examples include coal petrolium and gas

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