He current in a river is 1.0 meters/second. britney swims 300 meters against the current. if she normally swims with a speed of 2.0 meters/second in still water, how long does it take her to complete the trip

How have the competing explanations' experiments on atoms affected the development of the atomic model?

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.

Estimate the schwarzschild radius (in kilometers) for a mini-black hole formed when a superadvanced civilization decides to punish you (unfairly) by squeezing you until you become so small that you disappear inside your own event horizon. (assume that the your weight is 50 kg)