____________________
phenomenon
____________________
occurs
____________________
transmitting
light
is
refraction
,
____________________
consists
of
a
____________________
of
____________________
of
____________________
passing
from
one
medium
to
another
;
This
can
be
air
-
water
-
air
or
air
-
glass
-
air
.
For
____________________
,
if
____________________
put
a
straw
into
a
____________________
with
water
,
you
____________________
that
the
____________________
____________________
folds
.
This
is
____________________
____________________
passes
from
a
less
dense
____________________
to
a
____________________
one
.
