Answer :
The position vector is
![d\hat{i}-h\hat{j}](https://img.qammunity.org/2021/formulas/physics/high-school/payt49965a1e9a5pfcev21qno3st6zgjnt.png)
Explanation :
Given that,
Height = h
Distance = d
Suppose, A student throws a water balloon with speed v₀ from a height h = 1.98 mat an angle θ = 21° above the horizontal toward a target on the pound. The target is located a horizontal distance d = 65 in from the student's feet. Assume that the balloon moves without air resistance. Use a Cartesian coordinate system with the origin at the balloon's initial position
We know that,
The initially position vector is
![s_(i)=0\hat{i}+h\hat{j}](https://img.qammunity.org/2021/formulas/physics/high-school/nkysw1d1o55gyx7hu1btmlwxhhk4p6ci7g.png)
The final position vector is
![s_(f)=d\hat{i}+0\hat{j}](https://img.qammunity.org/2021/formulas/physics/high-school/eacwb0aqzy6rmyf9xpgrpkp9r75ic9vqqh.png)
We need to calculate the position vector
Using formula of position vector
![r=s_(f)-s_(i)](https://img.qammunity.org/2021/formulas/physics/high-school/b1ux3vqg38fhmbl8jpxejxxe0qy2s8s53t.png)
Put the value into the formula
![r=d\hat{i}+0\hat{j}-0\hat{i}-h\hat{j}](https://img.qammunity.org/2021/formulas/physics/high-school/7hf403yy3xmjsmjbpjae9alnd6q81p03y6.png)
![r=d\hat{i}-h\hat{j}](https://img.qammunity.org/2021/formulas/physics/high-school/34m91hwabrg0lpjpgl3qlvkt9ifo1qyoug.png)
Hence, The position vector is
![d\hat{i}-h\hat{j}](https://img.qammunity.org/2021/formulas/physics/high-school/payt49965a1e9a5pfcev21qno3st6zgjnt.png)