Sample 2-D kinematics problems

An airplane has a speed of 80 m/s and is diving at an angle of 30 degrees below the horizontal when the pilot releases a box full of food. The food travels a horizontal distance of 800 meters from the release point before it hits the ground.
1. How long is the food in the air?
2. How high above the ground was the plane when it released the food?
(easy version) Joe stands at the top of a cliff overlooking a lake. He drops a rock, and, 10 seconds later, hears a "splash!"
1. How high is the cliff?
answer, part 1 answer, part 2
(hard version) Joe stands at the top of a cliff overlooking a lake. He throws a rock horizontally outwards at speed v = 30 m/s, and, 10 seconds later, hears a "splash!"
1. How high is the cliff?
2. How fast did Joe throw the rock?
answer, part 1 answer, part 2 answer, part 3
(easy version) While standing at the base of a hill, Pam kicks a soccer ball.

The initial velocity of the ball was V = 30 m/s oriented 50 degrees above the horizontal. How far above the base of the hill does the ball land?
answer, part 1 answer, part 2 answer, part 3
(harder version) While standing on a level field, Pam kicks a soccer ball so hard that it leaves the field and lands on the slope of a nearby hill:

The initial velocity of the ball was V = 30 m/s oriented 50 degrees above the horizontal. How far above the level of the playing field does the ball land?
answer, part 1 answer, part 2 answer, part 3