Answer:
0.18 m
Step-by-step explanation:
The motion of the dart comprises horizontal and vertical components. Vertically, the initial velocity is 0 because the dart was thrown horizontally. Also, the vertical motion is under gravity. Using the equation of motion
![s = ut+(1)/(2)at^2](https://img.qammunity.org/2021/formulas/physics/college/lbngozdcx3diccg7a3coroebufsyynmmvy.png)
where
is the vertical distance from P,
is the initial velocity,
is the acceleration and
is time, we have
![s = 0*1.9+(1)/(2)9.8*0.19^2 = 0.17689 = 0.18 \text{ m}](https://img.qammunity.org/2021/formulas/physics/college/gkz7e2fcszo4cauq0xq5sedgmg8fz6olef.png)