4. If the 70 Kg runner of # 1 took 30 seconds to change its speed, then what force caused the change in momentum?

Now that the first three steps have been explained, identify the next three steps, in order. calculate the magnitude of r sum vector components calculate a and b magnitudes calculate the direction of r, calculate x,y components step 4 step 5 step 6

Astudent creates a model of a closed ecosystem by filling a glass tank half full with water, then adding 10 snails and two small aquatic plants. the next day, all the snails are dead. what is the most likely cause of their death?

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.