Which of the following is true about the position versus time graph of an object that comes to a stop, then remains at rest?
a. there is no change in slope.
c. the slope changes from positive to negative.
b. the slope changes to zero.
d. none of the above.

b its b bro

Explanation:

ice to water 1 water to vapour 2 latent heat

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s