Why is it important to apply critical thinking to spam e-mail?
a.
spam e-mail can contain malicious computer code and viruses.
b.
spam can be an attempt to commit fraud.
c.
it can be an attempt to get personal and financial information.
d.
all of the above

Light traveling in water, nwater = 1.33, strikes a plastic block at an angle of incidence of 51.4°; part of the beam is reflected and part is refracted. if the index of refraction of the plastic is 2.0, what is the angle made by the reflected and refracted beams?