3. The following position vs. time graph describes the motion of a squirrel running along a clothesline. Use this graph to answer the questions below. Provide a brief explanation of each answer. 54321 Jy 5 10 15 20 25 30 35 40 Time (s) Position (m) 77344 a) During what times is he running forward? Running backwards? Standing still? b) During what times is his speed the fastest? c) What is the total distance he traveled from t = 0 tot = 40 s? d) What is the total displacement he traveled from t = 0 to t= 40 s? e) What is his position at t= 12 s? f) What is his velocity at t = 12 s? g) What is his average velocity from t = 0 tot = 25 s? h) What is his average speed from t= 0 to t = 25 s? 4. Can speed be constant and velocity changing at the same time? Can velocity be constant and speed changing at the same time? If you answer yes to either question, give an example. If you answer no, explain why not. 5. It's a race against time! Terrorists have placed deadly explosives at a downtown location and it's up to you - a daring special agent to stop them and save the day. The explosives are 12 km from your current position, and you only have ten minutes to reach them before they detonate. The clock is ticking, and you have to do some fast calculations. a) If you're to reach the downtown location in time, what must your average velocity be, in km/hr, for the entire trip? b) You travel the first 6 km at a velocity of 60 km/hr. How many minutes does it take you? c) How much time remains? d) What velocity must you maintain for the final 6 km, so you can complete the trip in the time remaining? Make sure to use units of km/hr. You can also assume that, since you're a hero, you reach your destination in the nick of time.