The radioactivity of Earth can vary depending on the location and geological characteristics of different regions. However, a commonly used measure to estimate the overall radioactivity of Earth's crust is the specific activity of potassium-40 (K-40), which is a naturally occurring radioactive isotope. The typical specific activity of K-40 in Earth's crust is approximately 33 becquerels per kilogram (Bq/kg), where a becquerel represents one radioactive decay per second.

The exact radioactivity level of a rogue continental planet would depend on various factors such as its geological composition and history. However, it can be expected that a habitable rogue continental planet with oceans and continents would still possess some degree of natural radioactivity. Without a specific planetary model or data available, I cannot provide an exact number for the radioactivity of a rogue continental planet. The radioactivity levels in such a scenario would rely on the elements and isotopes present in the planet's crust and mantle. To determine the planetary temperature and the impact of radioactivity on habitability, a detailed analysis using advanced planetary modeling would be necessary. This analysis would consider factors like internal heat production, geothermal energy, greenhouse gases, and the balance between energy input from the host star and heat loss from the planet.

Determining the exact radioactivity level of a hypothetical rogue continental planet would still be a complex task, as various factors come into play. However, we can make an educated guess based on certain assumptions and approximations. Assuming this rogue continental planet is able to maintain habitable conditions due to the presence of ongoing radioactivity, we can estimate the radioactivity levels using the specific activity of radioactive isotopes found on Earth as a reference. Let's consider the specific activity of potassium-40 (K-40) as a representative radioactive isotope. Earth's crust has an average specific activity of around 33 becquerels per kilogram (Bq/kg) for K-40. We can assume a similar specific activity for the crust of the rogue continental planet. Now, to estimate the overall radioactivity level, we would need to consider the composition and size of the planet. Let's assume an Earth-like composition and similar crustal thickness for simplicity. Suppose the rogue continental planet has a mass and size comparable to Earth, which is approximately 5.97 x 10^24 kilograms. Assuming the crust represents a fraction of the total mass (similar to Earth), let's say around 1% of the total mass is crustal material, i.e., around 5.97 x 10^22 kilograms. Using the average specific activity of K-40, we can estimate the total radioactivity of the crustal material on the rogue continental planet. Multiplying the specific activity by the mass of the crust gives us: Total radioactivity = Specific activity (K-40) x Mass of the crust Total radioactivity = 33 Bq/kg x 5.97 x 10^22 kg This calculation would give us an estimation of the overall radioactivity present in the planetary crust, in terms of becquerels. However, please note that this is a simplified approximation, and the actual radioactivity of a rogue continental planet would require more detailed calculations and knowledge of specific geological processes and isotope distributions.