Answer the two questions by using the pictures, thanks!

Explanation:

The football was launched by the girl. This is, the girl applied a force over the football and it started to move.

Newton's second law of motion tell us that the net force on an object is proportional to the product of the the mass of the object and the acceleration it acquires.

Then, the force applied by the girl on the football caused it to accelerate: it passed from rest to have some speed.

The same happens to the baseball lauched by the boy. It accelerated due to the force applied by the boy.

The acceleration of each ball can be calculated using Newton's second law of motion:

Thus, if you assume that both the girl and the boy applied the same force to their respective balls, the baseball, which has less mass, would acquired a greater accelaration than the football.

After the football and baseball leave the students' hands, the only force acting on them is the force of gravity which is vertically downward.

If there was not gravitational and other forces acting after the sutdents launched the balls, they  would continue to travel in the same direction and with the same speed that it started to move.

Due to the gravitational force, the combination of the initial speed acquired by each ball, by the force applied by each student, and the downward acceleration after the balls left the students' hands make that the motion of the balls be parabolic.

what's the

a) the particles of the chair are strongly held together.