Which of the following changes igneous or sedimentary rock into metamorphic rock?

a.) heat and pressure
b.) heat and weathering
c.) water and weathering
d.) water and pressure

Hybrid instruments that play sounds that are part sampled and part synthesized are known as:

Vaccines are weakened forms of disease causing microorganisms, which are given to patients to prevent disease. after the vaccine is administered, the immune system responds by creating a(n) to recognize the a.) antibody, antibiotic b.) antigen, antibody c.)antibiotic, antibody d.)antibody, antigen

The earth's oceans are made up of chlorine, and trace elements. a) carbon, oxygen b) oxygen, silicon c) hydrogen, oxygen d) nitrogen, oxygen