According to Heisenberg's Uncertainty Principle, the product of uncertainty in position ($\Delta x$) and uncertainty in momentum ($\Delta p$) is greater than or equal to a constant ($\frac{h}{4\pi}$). The mathematical expression is: $\Delta x \cdot \Delta p \geq \frac{h}{4\pi}$ Given that the uncertainty in position is similar (equal) for both the electron and the Helium atom ($\Delta x_e = \Delta x_{He}$), the uncertainty in their momentum must also be equal to satisfy the principle, regardless of their masses. $\Delta p_{He} = \Delta p_e = 32 \times 10^5$ Note: Mass would only result in a difference if the question asked for uncertainty in velocity ($\Delta v$), since $\Delta p = m\Delta v$.