What is impulse and what is its magnitude when a golf ball is hit?

The mass of the golf ball is $m = 0.044 \text{ kg}$.
The initial velocity is $v_i = 0 \text{ m/s}$ (since it's initially at rest).
The final velocity is $v_f = 43 \text{ m/s}$.
The formula for impulse ($J$) is the change in momentum: $J = \Delta p = m v_f - m v_i$.

The direction of the impulse is in the direction the ball leaves the tee.
The magnitude of the impulse is $\boxed{\text{1.89 kg}\cdot\text{m/s}}$.
The direction of the impulse is in the direction the ball leaves the tee.

3.3:

From 3.2, the impulse $J = 1.892 \text{ kg} \cdot \text{m/s}$.
The contact time is $\Delta t = 3.4 \times 10^{-3} \text{ s}$.
The formula for average force ($F_{avg}$) is $F_{avg} = \frac{J}{\Delta t}$.

The magnitude of the average force is $\boxed{\text{556.5 N}}$.