To find the normal force exerted on the book, we need to consider the forces acting on the book and apply Newton's second law.

The forces acting on the book are:

1. Gravitational force (W) due to Earth's gravity, pulling the book downward.

2. Normal force (N) exerted by the slope, pushing the book perpendicular to the slope.

3. Horizontal force (F) applied to the book, keeping it in equilibrium.

Since the book is in equilibrium, the net force acting on it is zero. Therefore, we can write:

$$\sum F_y = N - W \cos 60\degree = 0$$

$$\sum F_x = F - W \sin 60\degree = 0$$

Solving the first equation for N, we get:

$$N = W \cos 60\degree$$

Substituting the weight of the book, $$W = mg = 2.0 \text{ kg} \times 9.8 \text{ m/s}^2 = 19.6 \text{ N},$$

we have:

$$N = 19.6 \text{ N} \times \cos 60\degree = \boxed{9.8 \text{ N}}$$

Therefore, the normal force exerted on the book by the slope is 9.8 N.