(adsbygoogle = window.adsbygoogle || []).push({}); Help!!! Planetary motion

Please help!

Planet X rotates in the same manner as the earth, around an axis through its north and south poles, and is perfectly spherical. An astronaut who weighs 946 N on the earth weighs 920 N at the north pole of Planet X and only 854 N at its equator. The distance from the north pole to the equator is 1.889×104 km , measured along the surface of Planet X.

How long is the day on Planet X? Take free fall acceleration on Earth to be 9.80 m/s^2

I'm totally stuck and I've being trying to do this for about an hour in many different ways. The equation T^2=(4*pi^2*r^3)/G*M doesn't seem to work. I don't know what I'm doing wrong, and I don't understand what to do with the two different weights at the pole and equator. :(

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# Homework Help: Help Planetary motion

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