The formula for the period of a simple pendulum is \( T = 2\pi \sqrt{\frac{L}{g}} \). Here, \(L\) represents the pendulum's length, and \(g\) denotes the acceleration due to gravity. While gravity decreases slightly at an altitude of \(R\) above Earth's surface, for small height variations, the period is expected to be approximately constant even at \(2R\). Therefore, \(T_1 = T_2\).