Answer:
252 Joules.
Step-by-step explanation:
From the question, we can deduce that baby carriage isn't moving and as such possess energy due to its position. This ultimately implies a gravitational potential energy.
Potential energy can be defined as an energy possessed by an object or body due to its position.
Mathematically, potential energy is given by the formula;

Where, P.E represents potential energy measured in Joules.
m represents the mass of an object.
g represents acceleration due to gravity measured in meters per seconds square.
h represents the height measured in meters.
Given the following data;
Height = 21m
Weight of carriage with baby = 12N

But we know that weight = mg = 12N
Substituting into the equation, we have;


Therefore, the energy possessed by the carriage is 252 Joules.