The of the indus river valley is well known for their carefully planned city sites built in organized grids.
a. harappan civilization
b. shang dynasty
c. olmec civilization
d. egyptian civilization

The Harappan civilization of the Indus River Valley is well known for their carefully planned sites built in organized grids. The correct option in regards to the given question is option "a".Harran civilization is part of Indus Valley Civilization. This was a civilization that flourished beside the river Indus and had excess amount of  agricultural production and had great commerce structure as well. The bricks that were used to construct the buildings of Harrapan civilization was made from red sand, stones and clay. These materials were baked at very high temperature to create solid bricks.

The harppan civilization  of the indus river valley for their carefully planned city sites built in organized grids.

Don’t use up to much of them it leads to pollution

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