Answer:
There are about six to seven million cones in a human eye and are most concentrated towards the macula. Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color.
A and C
Imagine u are shooting a laser pointer at a mirror this is pretty much what it is
Answer:
a) For P: 
For Q: 
b) For P:

for Q:

c) As the distance from the axis increases then speed increases too.
Explanation:
a) Assuming constant angular acceleration we can find the angular speed of the wheel dividing the angular displacement θ between time of rotation:

One rotation is 360 degrees or 2π radians, so θ=2π

Angular acceleration is at every point on the wheel, but speed (tangential speed) is different and depends on the position (R) respect the rotation axis, the equation that relates angular speed and speed is:

for P:

for Q:

b) Centripetal acceleration is:

for P:

for Q:

c) As seen on a) speed and distance from axis is
because ω is constant the if R increases then v increases too.
Answer:
true
Explanation:
a wheelbarrow has its load situated between the fulcrum and the force the wheel Barrow is 2nd class because of its resistance between the force and the axis