What country shares borders with both belarus and romania

Volcanic irruption is most likely to be violent when a) volcanoes near to the sea b) the neck of the volcano is sealed by a plug c) the lava is viscous d) the lava reaches the surface through a fissure e) the volcano is on the ocean floor

Which of the following is not considered one of the four major oceans (1 point)

The 5th term in a series of even number that begin 3x