A sound wave is sent at the bottom of a sea. If the echo is heard after 2 sec- calculate the depth of the sea. The speed of sound in water is 1500 m/s.

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656 nm(red) and 486 nm (blue). light from a hydrogen lamp illuminates a diffraction grating with 520lines/mm , and the light is observed on a screen 1.5m behind the grating. part a what is the distance between the first-order red and blue fringes? express your answer to two significant figures and include the appropriate units.

In which of the following cases is work being done on an object? question 2 options: pulling a trailer up a hill carrying a box down a corridor suspending a heavy weight with a strong chain pushing against a locked door

Asap time is ! best answer gets compose at least one well-developed paragraph on the following: define the term concurrent powers, and give an example of a concurrent power of government.