Can you me with this high school problems? About projectile motion

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lanvin
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Homework Statement



I just did this question, and I just want to make sure I did it right... Can u run through it and notify me of any errors?


Homework Equations



Here is the question:
http://i299.photobucket.com/albums/mm286/lanvin12/333-1.jpg

The Attempt at a Solution



this is what I did...

V(x) = V(bx) - V(ax) = [ (4.4m/s) sin 31° ] - [ (7.8m/s) sin 25° ] = 1.030262m/s

V(y) = V(by) + V(ay) = [ (4.4m/s) cos 31° ] - [ (7.8m/s) cos 25° ] = 10.840736 m/s

V² = V(x)² + V(y)² = 10.8² + 1.03² + 118.5
V = √118.5 = 10.88

A = V / t = 10.88 / 8.55 = 1.28m/s²


tan theta = 10.84 / 1.030 = 10522
theta = tan^(-1) 10.52230 = 84.57°

therefore, the bird's acceleration was 1.3 m/s² [85° S of E]

is that right? Was I supposed to use TOA? Significant digits ok?
Any mistakes...?
 
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I don't think it is right that the average acceleration is 85o S of E. If that is the case, wouldn't the bird be flying south now?