Arectangular box has the dimensions shown. (a) determine the angle bac to the nearest degree. (b) determine the area of the triangle abc to the nearest tenth of a cm. useful relations: law of cosines: c2 a2 b2 2ab cos n)c2=a2+b2? 2ab* heron's formula for triangular area: a=\sqrt{p(p-a)(p-b)(p-c)}a=p(p? a)(p? b)(p? c), where p=\frac{a+b+c}{2}

If you were designing a bumper for a car, would you prefer it to exhibit elastic or plastic deformation? why? consider the functions of a bumper in both a minor "fender-bender" and a major collision.

What precautions should you take to prevent injuries when dealing with heavy loads?

Consider a large isothermal enclosure that is maintained at a uniform temperature of 2000 k. calculate the emissive power of the radiation that emerges from a small aperture on the enclosure surface. what is the wavelength ? , below which 10% of the emission is concentrated? what is the wavelength ? 2 above which 10% of the emission is concentrated? determine the wavelength at which maximum spectral emissive power occurs. what is the irradiation incident on a small object placed inside the enclosure?