Cut a 7-inch-diameter circle out of card stock. Draw a spiral on the circle as shown. Next, use the scissors to cut along the lines you drew starting on the outside and ending in the center. Use the hole punch or scissors to make a hole at the middle of the spiral and attach the thread with a knot. Tie the other end of the thread loosely around the center of the stick so you can suspend the spiral in the air. Fill the pot with 2 inches of water. Heat the water until it boils, and then turn off the heat source. Let the pot sit for 4 minutes. Holding the ends of the stick with the spiral attached, position the bottom of the spiral right above the top of the pot so it’s not touching the water. Describe what happens.

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Consider the motion of the balloon and its air contents in terms of momentum. in step 1 above, the total momentum of the balloon and its contents was zero. recall that momentum = mv. both the balloon and the air inside it had a velocity of zero and therefore the total momentum was zero. now think about what happened when the air escaped from the balloon. a certain mass of air accelerated in one direction. in order to keep the total momentum of the system zero, the balloon itself (which has mass) had to accelerate in the opposite direction. use this scenario to you explain why the soda can rotates when the water squirts out of the escape holes. what was your hypothesis concerning the water-filled can? according to your data, do you think your hypothesis was correct? (be sure to refer to your data when answering this question.) summarize any difficulties or problems you had in performing the experiment that might have affected the results. describe how you might change the procedure to avoid these problems. give at least one more example of newton's third law in everyday life.

Acommon kind of mechanical weathering is called