1. A train is traveling on a straight section of track at constant speed. In 60 seconds it covers a distance of 1800 meters. What is the speed of the
train?

When an object travels at a constant speed with zero acceleration it is known as uniform rectilinear motion. Then its velocity is given by:

v = d / t

Where d is distance and t is time. Evaluating:

v = 1800 m / 60 s

cell differentiation  is how generic embryonic  cells  become specialized  cells. this occurs  through a process called gene expression. gene expression is the specific combination of genes that are turned on or off (expressed or repressed), and this is what dictates how a  cell  functions.

explanation:

80cm/s.

24cm/s.

53.3cm/s.