PLEASE HELP ASAP! What wave measurement represents how fast the disturbance of the wave is moving?

If the moon has a diameter of 2,159.14 miles, what is the maximum distance that it could be observed by the naked eye with enough detail that you could distinguish it from other celestial bodies (assuming that you have 20/20 vision)

Abatter hits the baseball a with an initial velocity of v0 = 110 ft/sec directly toward fielder b at an angle of 23° to the horizontal; the initial position of the ball is 2.2 ft above ground level. fielder b requires 0.44 sec to judge where the ball should be caught and begins moving to that position with constant speed. because of great experience, fielder b chooses his running speed so that he arrives at the “catch position” simultaneously with the baseball. the catch position is the field location at which the ball altitude is 8.4 ft. determine the velocity of the ball relative to the fielder at the instant the catch is made.

What are atoms of the same element with varying number of neutrons