To solve for the initial velocity $v_0$ in the given equation:

$1.39 = \frac{2 v_0 \sin \theta}{9.8}$

we can rearrange the equation to isolate $v_0$.

Step 1: Multiply both sides by $9.8$

$1.39 \times 9.8 = 2 v_0 \sin \theta$ $13.622 = 2 v_0 \sin \theta$

Step 2: Divide both sides by $2 \sin \theta$

$v_0 = \frac{13.622}{2 \sin \theta}$ $v_0 = \frac{13.622}{2 \sin \theta}$ [ v_