Waves in a lake are 6 m apart and pass a
person on a raft every 2 s. What is the
frequency, period, wavelength, and speed of
the waves?

Which word expression describes how much to calculate pressure

What do we mean by the event horizon of a black hole?

Aprotein molecule in an electrophoresis gel has a negative charge.the exact charge depends on the ph of the solution, but 30 excesselectrons is typical. what is the magnitude of the electric forceon a protein with this charge in a 1500 n/c electric field?