Aball is dropped from a boat so that it strikes the surface of a lake with a speed of 16.5 fps. while in the water the ball experiences an acceleration of a=10−0.8v, where a and v are expressed in fps^2 and fps respectively. knowing the ball takes 3 sec to reach the bottom of the lake, determine the following:
a. the depth of the lake
b. the speed of the ball when it hits the bottom of the lake

"curse these trig-loving pirates! " devora mutters as she looks at the map. then, after thinking for a moment, she walks back to the entrance of the secret cave, measuring 48 meters along the way. after performing a calculation, devora walks back to the empty treasure, faces the entrance, and turns a certain number of degrees to her left before walking 89 meters to the treasure. supposing that the angle at the cave entrance is acute and that devora's calculations were correct, how many degrees did she turn?