Why is the gravity on Earth greater than the gravity on Mars? (HELP will mark as Brainliest!!!) a
. Mars has a smaller radius than Earth.
b
Mars has less mass than Earth.
c
Earth has less surface area than Mars.
d
Earth has a thicker atmosphere than Mars.

Acarpenter builds an exterior house wall with a layer of wood 2.9 cm thick on the outside and a layer of styrofoam insulation 2.3 cm thick on the inside wall surface. the wood has k=0.080w/(m⋅k), and the styrofoam has k= 0.010 w/(m⋅k). the interior surface temperature is 19.0 ∘c , and the exterior surface temperature is -15.0 ∘c . a.)what is the temperature at the plane where the wood meets the styrofoam? celsius b.)what is the rate of heat flow per square meter through this wall? /m^2