On earth stp is based on the average atmospheric pressure

Question

Solve the each part of following question given below:

Question: On earth, STP is based on the average atmospheric pressure at the surface and on a phase change of water that occurs at an easily produced temperature, being only slightly cooler than the average air temperature. The atmosphere of Venus is almost entirely carbon dioxide (CO₂), the pressure at the surface is a staggering 93 atm, and the average temperature is 470^oC. Venusians scientists, if they existed, would certainly use the surface pressure as part of their definition of STP. To complete the definition, they would seek a phase change that occurs near the average temperature. Conveniently, the melting point of the element tellurium is 450^oC. The radius of a CO2 molecule is 1.5×10¹⁰ m.

Part I: What is the rms speed of carbon dioxide molecules at Venusians STP based on this phase change in tellurium?

Part II: What is the mean free path of carbon dioxide molecules at Venusians STP based on this phase change in tellurium?

I am not able to get the correct answer please help me and express your answer to two significant figures and include the appropriate units.