The radius of the circle having its centre at $(0, 3)$ and passing through the foci of the ellipse $\frac{x^2}{16} + \frac{y^2}{9} = 1$ is:

  • A
    $3$
  • B
    $3.5$
  • C
    $4$
  • D
    $\sqrt{12}$

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Let $M = \{(x, y) \in \mathbb{R} \times \mathbb{R} : x^2 + y^2 \leq r^2\}$,where $r > 0$. Consider the geometric progression $a_n = \frac{1}{2^{n-1}}$,$n = 1, 2, 3, \ldots$. Let $S_0 = 0$ and,for $n \geq 1$,let $S_n$ denote the sum of the first $n$ terms of this progression. For $n \geq 1$,let $C_n$ denote the circle with center $(S_{n-1}, 0)$ and radius $a_n$,and $D_n$ denote the circle with center $(S_{n-1}, S_{n-1})$ and radius $a_n$.
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$(A)$ $k + 2l = 22$ $(B)$ $2k + l = 26$ $(C)$ $2k + 3l = 34$ $(D)$ $3k + 2l = 40$
$(2)$ Consider $M$ with $r = \frac{(2^{199}-1)\sqrt{2}}{2^{198}}$. The number of all those circles $D_n$ that are inside $M$ is
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For the circle $C$ with the equation $x^2+y^2-16x-12y+64=0$,match the List-$I$ with the List-$II$ given below.
List-$I$List-$II$
$(i)$ The equation of the polar of $(-5, 1)$ with respect to $C$$(A)$ $y = 0$
$(ii)$ The equation of the tangent at $(8, 0)$ to $C$$(B)$ $y = 6$
$(iii)$ The equation of the normal at $(2, 6)$ to $C$$(C)$ $x + y = 7$
$(iv)$ The equation of the diameter of $C$ through $(8, 12)$$(D)$ $13x + 5y = 98$
$(E)$ $x = 8$

The correct match is:

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