.) A student has a sample of ocean water that they take to science class. What steps could be taken to determine to classify the ocean water as
a suspension, solution, element, or compound?
A)
Examine the pH of the sample. If the pH is exactly
neutral, it is a pure substance that is a compound.
B)
Evaporate the water. If salt is left behind the sample
is a mixture that can be defined as a solution.
Let the sample settle. If the salt settles to the
bottom, it is a mixture that is classified as a solution
Observe the diffraction of light as it moved through
D) the sample. If light does not scatter, it is a pure
substance that is elemental.

the velocity you are looking for is made up of two parts: horizontally velocity, vh, and its vertical velocity, vv. the actual velocity of the ball will be these two parts added together, and because velocity is a vector then they will need to be added vectorially.  

neglecting air resistance etc etc.,  

the horizontal velocity component will be constant (because there is no accelerating force in the horizontal direction.  

vh = 8 ms-1  

the vertical velocity component has an accelerating force: 'g'.  

using v = u +at where a = g = 9.81 ms-2.  

the vertical component of velocity, vv = 0 + gt = vv =9.81 x 2  

vv = 19.62 ms-1 . the zero appears because the virtical component of velocity at time t=0 is zero. remember, the ball was thrown horizontally.  

how fast it will be moving (it actual path (being a parabola )) will be the vector sum of these two.  

adding vectorally gives: -  

v = sqr root (8^2 + 19.62^2) = sqr root(64+384.9) = 21.18 or 21.2 ms-1

pecialized keyboards

one "light year" is the distance that light travels, through vacuum, in one julian year.   that's 365.25 days, of 24 hours each.