1.)An object moves along a straight line. First it travels at a velocity of 12m/s for 5s and then continues at the same direction with 20m/s for 3s. What is its average speed? 2.)A car travels along the x-axis for 4s at an average velocity 10m/s and 2s with an average velocity 30m/s and finally 4s with an average velocity 25m/s. What is its average velocity across the whole path?

Do you agree with scientist’s prediction about the warming of alaska and other polar regions?

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.

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer