HEL I DONT UNDERSTAND In a breakwater, waves break at a rate of 12 waves per minute. If their length is l = 50m find: a) the period of the wave b) the velocity of propagation of the wave c) the distance at which the wave propagates in a period of three periods

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it