Shield volcanoes form from lava; composite volcanoes form from lava. a) low; high b) high; low

The study of rocks is called petrology. There are different types of rocks and these are granite, marble, igneous and etc.

The correct answer is mentioned below.

A mountain that has a hole in it that is filled with lava. Volcanoes can be active or dormant.

According to the question, Shield volcanoes form from HIGH-viscosity lava; composite volcanoes form from LOW-viscosity lava.

Hence, the correct answer is high and low.

For more information about the volcanos, refer to the link:-

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