Task $5$: Law of Universal Gravitation

You are on a deep space mission to search for Earth$-$like planets. Your crew locates a possible planet and with scanners find the radius to be $7\mathrm{.}5$ x $106$ m$.$ A team lands on the surface. There, they hang a $1\mathrm{.}0$ kg mass from a spring scale. It reads $8\mathrm{.}5$ N$.$

a$)$ Determine the mass of the planet using Newton$$s Law of Universal Gravitation.

b$)$ Describe whether an astronaut standing on this new planet weighs more, less, or the same as on Earth. Show your work.