Two ships, a and b, leave port at the same time. ship a travels northwest at 15 knots and ship b travels at 20 knots in a direction 40° west of south. (1 knot = 1 nautical mile per hour) (a) what is the magnitude the velocity of ship a relative to b? knots (b) what is the direction of the velocity of ship a relative to b? ° east of north (c) after what time will the ships be 160 nautical miles apart? h (d) what will be the bearing of b (the direction of b's position) relative to a at that time? ° west of south

Uranium has two naturally occurring isotopes. 238u has a natural abundance of 99.3% and 235u has an abundance of 0.7%. it is the rarer 235u that is needed for nuclear reactors. the isotopes are separated by forming uranium hexafluoride uf6, which is a gas, then allowing it to diffuse through a series of porous membranes. 235uf6 has a slightly larger rms speed than 238uf6 and diffuses slightly faster. many repetitions of this procedure gradually separate the two isotopes. what is the ratio of the rms speed of 235uf6 to that of 238uf6? express your answer to five significant figures.