Which factors contribute to changing igneous and sedimentary rocks into metamorphic rocks

Heat & pressure both contribute to changing igneous and sedimentary rocks into metamorphic rock.

Opposition to the nra came to a head in 1935, when the conservative supreme court declared the agency unconstitutional, claiming the nra gave the executive branch regulatory powers that belonged exclusively to congress. this decision began a series of court decisions that overturned key elements of the new deal.