2. Barbara can swim at 4 Km/h in still water. She wishes to swim across a river to a point di- rectly opposite from where she is standing. The river is moving at a rate of 5 Km/h. Explain, with the use of a diagram, why this is not possible.

3. The graph below shows the displacement vs time of a student leaving the NSCI 110 after physics class walking towards the cafeteria for lunch (assume a 1-D motion) At some point between NSCI 110 and the cafeteria, the student realizes they have left their cell phone in the classroom, so they turn back to get it. Displacement vs Time 120 100 nol Velocity vs Time 80 1.5 60 40 30 60 90 120 150 180 210 20 -1.5 30 60 90 120 150 180 210 Time (s) a. How far did the student walk before realizing that they left their cell phone in the classroom? How long did this take? (2 marks) b. With what velocity did the student walk back to the classroom? (2 marks) c. Fill out the velocity vs time graph above. (2 marks) Distance (m)

1. Suppose that the velocity of a particle in motion is given by v(t) = 44t² +²+1 feet per second, where t is in seconds from now. Find the position of the particle after 5 seconds.

Can I please get some help with this problem. I can't seem to figure this out. thank you!

2. At an archery contest, a large circular target 5 ft in diameter is laid flat on the ground with the bull's- eye exactly 180 yd (540 ft) away from the archers. Marion draws her bow and shoots an arrow at an angle of 25° above horizontal with an initial velocity of 150 ft/sec (assume the archers are standing in a depression and the arrow is shot from ground level). a) What was the maximum height of the arrow? b) Does the arrow hit the target?

Said can swim at 5 m/s in still water. He wishes to swim across a river 200m wide to a pointdirectly opposite from where he is standing. The river flows westward at 4 m/s and he is standingon the south bank of the river.  a) Draw a diagram. b) What is Said’s speed relative to the ground? c) In what direction must Said head? d) How long does it take to cross the river??

11. A person is standing 300 feet from the launch point of a hot air balloon. The hot air balloon starts to come back down at a rate of 18 feet per second. (a) What is the rate at which the distance between the person and the hot air balloon is changing at the moment the hot air balloon is 400 feet in the air? (b) What is the rate at which the angle of elevation (the angle created by the ground and the person's line of site to the balloon) is changing at the moment the hot air balloon is 400 feet off the ground?

3. Sara can swim at a speed of 3.5 km/h in still water. She encounters a current of 1.25 km/h while trying to cross a river. What is her resultant velocity? Include a vector diagram and direction.