Just under half the oil that enters ocean water comes from natural oilseeps on the ocean floor. Just over half the oil in the oceans comes from human activities. Which human activity contributes the most oil to the oceans?
O
transporting oil over the ocean surface
drilling for oll on the ocean floor
O polluting land with oil that reaches the oceans in runoft
polluting air with oil that reaches the ocean in precipitation

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? question 2 options: the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the cold balloon expands and rises. the warm balloon shrinks and sinks. the warm balloon expands and rises. the cold balloon shrinks and sinks.