light that has a frequency of 1.5 x 1015 Hz.

Answer 1

It would help if you proofread your questions before you posted them.

Online, “*” is used to indicate multiplication to avoid confusion with “x” as an unknown.

Online "^" is used to indicate an exponent, e.g., x^2 = x squared.

f = 1.5(what?) * 10^15

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