[填空题]
A boat can travel 2 2l( mummju:157t;ee7d8o xeyw2lt r pb 4- e4gmrbk)y.30$ \mathrm{~m} / \mathrm{s}$ in still water.
(a) If the boat points its prow directly across a stream whose current is 1.20$ \mathrm{~m} / \mathrm{s}$ , what is the velocity (magnitude and direction) of the boat relative to the shore? magnitude direction $^{\circ}$
(b) What will be the position of the boat, relative to its point of origin, after 3.00 s? (See Fig. below)diraction = awayfrom the starting point,angle = $^{\circ}$ relative to the shore
