During one year a population of blue jays has zero population growth. which must be true about the blue jay population at the end of the year compared to the beginning of the year?

Hello there!

the fact that the population has zero population growth over a year means that, if at the start of the year the population was X, at the end of the year the population, Y, can't be bigger than X.

Then the relation between the population at the end of the year, Y, and the start of the year, X, is:

Y ≥ X

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.