Answer:

Explanation:
Let x be the distance to the shore
From trigonometry properties:

Answer:
v (speed) = S / t = 4 * 400 m / (6 * 60 sec) = 4.4 m/s
The average velocity is zero because there is no net vector displacement.
Answer: C. unknown element he predicted would have properties similar to those of aluminum.
Explanation: Mendeleev arranged the elements in order of increasing atomic masses. He left spaces for the elements that were predicted to exist, but were not discovered.
One space was left below Aluminum where an element of mass 70 was predicted to exist with properties similar to Aluminum. It was referred to as eka-Aluminum.
Later it was named as gallium.
It would do exactly what a rock or a frisbee does when you toss it.
After the engines cut off, it couldn't get any more energy from
anywhere, and after that, as it pushed air aside to get through,
and had air molecules scraping against it, those would slowly
rob kinetic energy from it. Sooner or later it would run out of
kinetic energy, start falling, and it would eventually make either
a big 'SPLOOSH' or else a big 'CRUNCH', depending on exactly
where it returned to Earth's surface.