Has a skateboard. your gonna have to give more details the. that just one .
Answer:
Any incident ray traveling parallel to the principal axis of a converging lens will refract through the lens and travel through the focal point on the opposite side of the lens. ... These rays of light will refract when they enter the lens and refract when they leave the lens.
Hope this helps...
A) f = 1.8 rev/s = 2 Hz
<span>T = 1 / f = 0.55s
B) not really sure..srry
C) </span><span>T = 2 pi √ ( L / g ) </span>
<span>0.57 = 2 x 3.14 x √ ( 0.2 / g )
</span><span>
g = 25.5 m/s²
</span>
Hope this helps a little at least.. :)