On a bus traveling north at 20.0m/s, a child stands up and walks towards the back of
the bus at 1.3m/s. What is the child's resultant velocity?

Explanation:

Taking north to be positive:

v = 20.0 m/s − 1.3 m/s

v = 18.7 m/s

The resultant velocity is 18.7 m/s north.

answer: the rock sample is a sedimentary rock.

explanation:

it is given that:

mass of rock sample, m = 2.7 g

volume of rock sample,

so, density of rock sample will be

since, the density of rock sample is . hence, the rock sample is a sedimentary rock, whose densities varies between .

not moving. pos accel,