What is the final velocity, in meters per second, of a freight train that accelerates at a rate of 0.085 m/s2 for 7.5 min, starting with an initial velocity of 3.4 m/s

The de broglie relation λ=h/p can be rewritten in terms of the wave number k as p=kℏ. recall that wave number is defined by k=2π/λ. using the fact that λ=v/f, find the wave numbers k1 and k2 corresponding to frequencies f1 and f2. express your answer as two expressions

Automobile fuel efficiency is often measured in miles that the car can be driven per gallon of fuel (mpg). heavier cars tend to have lower fuel efficiencies (lower mpg ratings). which variable (weight or fuel efficiency) is most naturally considered the explanatory (predictor) variable in this context?

Gordon is going for a run through the park, but it is cold outside. the low outside temperature could affect his personal safety.