Argon monatomic in nature because it is a noble gas and has completely filled shells and thus does not form a bond with other elements.
Riley can either change the surface area of the object or can change the slipperiness of the material.
I think that the sun is the center of the universe, not a human being. Everything revolves around the sun, not someone. U know when to sleep, when the time is, and when to wake up based on the sun. All the planets revolve around it. This is why I think the sun is the center of the universe, not a human being.
Speed in km/hr = 15 x 18
------------
5
= 54 km/hr.
Hope this helps!
