Questions: r = [4.0 cm + (25 cm/s^2) t^2] i + (5.0 cm / s) t j t=0 r=4.0 cm t=2.0

La posición $\vec{r}$ está dada por: $$\vec{r} = \left[4.0 \, \text{cm} + \left(\frac{25 \, \text{cm}}{\text{s}^2}\right) t^2 \right] \hat{i} + (5.0 \, \text{cm/s}) t \hat{j}$$

Para $t = 0$: $$\vec{r}(0) = \left[4.0 \, \text{cm} + \left(\frac{25 \, \text{cm}}{\text{s}^2}\right) (0)^2 \right] \hat{i} + (5.0 \, \text{cm/s}) (0) \hat{j} = 4.0 \, \text{cm} \hat{i}$$

Para $t = 2.0$ s: $$\vec{r}(2.0) = \left[4.0 \, \text{cm} + \left(\frac{25 \, \text{cm}}{\text{s}^2}\right) (2.0)^2 \right] \hat{i} + (5.0 \, \text{cm/s}) (2.0) \hat{j}$$ $$\vec{r}(2.0) = \left[4.0 \, \text{cm} + 100 \, \text{cm} \right] \hat{i} + 10.0 \, \text{cm} \hat{j}$$ $$\vec{r}(2.0) = 104.0 \, \text{cm} \hat{i} + 10.0 \, \text{cm} \hat{j}$$

$\boxed{\vec{r}(2.0) = 104.0 \, \text{cm} \hat{i} + 10.0 \, \text{cm} \hat{j}}$