I would go with the last two because they are the same please give me brainiest if i am right
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A) use v=u+at for both
First section, v=27, u=0, a=2.4. You should get 11seconds.
Second section, v=0, u=27, a=-1.3. You should get 21seconds.
This means that the total time is 22seconds.
b) You can either use s=ut+0.5at^2 or v^2=u^2+2as. Personally, I would use the second one as you are not relying on your previous answer.
First section, v=27, u=0, a=2.4. You should get 152m.
Second section, v=0, u=27, a=-1.3. You should get 280m.
This makes your overall displacement 432m.
<span>Without plate tectonics, new mountain belts could not form. Earth would be a Waterworld with occasional shield volcanoes emerging briefly above the waves. If regular catastrophic convective overturn occurred, as on Venus, life would have a precarious foothold indeed.
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