1. **State the problem:** We have a family of parabolas defined by a general equation involving $n$, $x$, and $y$. For $n=1,2,3$, the parabolas are graphed, all opening upward with vertex near $(0,1)$. We need to find which equation among the options fits all $n \geq 1$.
2. **Analyze the vertex:** The vertex is near $(0,1)$ for all parabolas, so the equation should have a constant term $+1$.
3. **Analyze the shape and width:** The parabola for $n=1$ is the narrowest and closest to the y-axis, $n=2$ is wider, and $n=3$ is the widest. This means as $n$ increases, the parabola becomes wider (less steep).
4. **Check each option:**
- A. $y = nx^2 + 1$: As $n$ increases, the parabola becomes steeper (narrower), which contradicts the graph.
- B. $y = \frac{1}{n}x^2 + 1$: As $n$ increases, $\frac{1}{n}$ decreases, so the parabola becomes wider, matching the graph.
- C. $y = x^2 + n$: Vertex moves up as $n$ increases, contradicting vertex at $(0,1)$.
- D. $y = -nx^2 + 1$: Parabolas open downward, contradicting upward opening.
- E. $y = -\frac{1}{n}x^2 + 1$: Parabolas open downward, contradicting upward opening.
5. **Conclusion:** The correct general equation is
$$y = \frac{1}{n}x^2 + 1$$
which is option B.
**Final answer:** B
Parabola Family A0Fa24
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