What color of light in the visible spectrum appears brightest? does this mean that it is the highest energy light?

Aperson stands on a platform, initially at rest, that can rotate freely without friction. the moment of inertia of the person plus the platform is ip. the person holds a spinning bicycle wheel with its axis horizontal. the wheel has moment of inertia iw and angular velocity ωw. take the ωw direction counterclockwise when viewed from above. part a what will be the angular velocity ωp of the platform if the person moves the axis of the wheel so that it points vertically upward?

You win the lottery and decide to impress your friends by exhibiting a million-dollar cube of gold. at the time, gold is selling for $ 426.60 per troy ounce, and 1.0000 troy ounce equals 31.1035 g. -how tall would your million-dollar cube be? en cm

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.