C. Shield Volcano.. think of Hawaiian volcanoes,they are basaltic eruptions, very effusive and unexplosive and are characterised by slow lava movement and very little tephra from the eruption. The basalt erupted is very hard, dense rock and so can be built up easily.
B. sulfur tetrafluoride + water → hydrogen fluoride + sulfur dioxide
In the nucleus, the part on the cell that contains all the genome
