1) 260 km/h
Let's use the following convention:
positive x-direction = east
positive y-direction = north
Here we have to find the north component of the velocity's airplane, which means we have to find its y-component.
We can use the formula:
where
v = 750 km/h is the magnitude of the plane's velocity
is the angle between the direction of the plane and the positive x-axis
Substituting,
2) north of east
In order to find the direction of flight, we have to consider that the vector representing the displacement of the plane is the hypothenuse of a right triangle, of which the displacements along the east and north direction are the sides.
Therefore, we have
is the displacement towards east
is the displacement towards north
Therefore, the angle that gives the direction is given by
And substituting,
and this angle is measured north of east.
You didn't attach the figure. Your text is incomplete. And you never got around to asking a question. Other than that, we're on it.
Let
dV = dt = water is flowing in at a rate of 12 ft3 / min.
h = the depth of the water.
dh / dt = the rate of change of the depth.
First you must find the volume of the cone as a function of "h". Then you must derive the volume of the cone with respect to time. Finally clear dh / dt.
I attach the solution.