Vectors. Adding, subtracting, and velocity questions

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The discussion revolves around various physics problems related to vectors, displacement, and velocity. Key questions include finding the angle of final displacement for a woman's walk, determining vector values for equations involving a, b, and c, and calculating the average acceleration of a bicyclist over a 12-second interval. The user has successfully solved most parts but is seeking assistance specifically with the angle and magnitude of average acceleration in question 5, as well as the time and speed of a ball rolling off a table in question 6. Overall, the user expresses confusion about certain calculations and appreciates any help provided.
Matt12345
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So I have a few problems that I need help with. Any help would be greatly appreciated as I am new here and stumped.

1. A woman walks 220 m in the direction 27 degrees east of north, then 205 m directly east.
(a) find the magnitude (finished it).
362.5 m

(b) Find the angle of her final displacement from the starting point.
?

(c) Find the distance she walks (finished it).
425

2. Suppose a-b=2c, a+b=9c, and c=5i+3j. (***NOTE: all "a","b", and "c" have directional arrows above them I just didn't know how to put them there. The i and j have ^ above them as well).

(a). What is a?
?

(b). What is b?

5. At one instant a bicyclist is 35 m due east of a park's flagpole, going due south with a speed of 11 m/s. Then, 12 s later, the cyclist is 50 m due north of the flagpole, going due east with a speed of 12 m/s. For the cyclist in this 12 s interval, find each of the following.

(a) displacement (solved)
magnitude = 61 m
direction = 55 degrees north of west

(b) average velocity (solved)
magnitude =5.08 m/s
direction = 55 degrees north of west

(c) average acceleration
magnitude = ? m/s^2
direction = ? degrees north of east

6. A ball rolls horizontally off the edge of a tabletop that is 2.00 m high. It strikes the floor at a point 1.57 m horizontally away from the table edge. (Neglect air resistance.)

(a) How long was the ball in the air?
? s

(b) What was its speed at the instant it left the table.
?


I am sorry there are so many, I got the majority of them but was very confused on these. At first I thought I new how to do 6 but then I realized that I didn't have the instant velocity in the x direction. All help is greatly appreciated. Thanks again.
 
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I have answered all except question 5 part c. I got the acceleration, and the angle, but I cannot figure out the magnitude of the average acceleration. Any help?
 
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