A(n) statement is best to use when refining your hypothesis. direct defining if then simple they have been answered on here before but there is three different answers amongst them.

An if-then statement is best to use when refining a hypothesis. This can be understood by the following example. "Soil erosion and forest cover are related to each other", a very general statement. "Soil erosion is less in areas with forest", this is a bit specific but lacks the direction. "If forest cover goes down, then the soil erosion increases", this is a ore refined testable version of the proposed hypothesis.

is this for the e2020 class

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.