The position of a certain particle depends on time according to the following equation.
x(t)=t^-5.2t+1.2
x is in meters and t is in seconds.
a) find the displacement and average velocity for the interval 3.4s less than or equal to t less than or equal to 4.5a

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