During takeoff, a plane accelerates at 4 m/s and takes 40 s to reach takeoff speed. what is the velocity of the plane at takeoff?

This is the substance(s) formed in a chemical reaction.

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)

Which accurately compares concave and convex lenses?