Answer:
21/42
Step-by-step explanation:
Hope this helps :)
The Planck–Einstein relation

gives that E, the photon energy, is equal to h, Planck's constant, times <span>ν</span>, the frequency.
We can solve the equation in terms of frequency to get

We substitute our given energy,

, and Planck's constant,

.
Answer:
84.6 minutes
Step-by-step explanation:
94% of 90 minutes =
= 0.9 * 94 minutes
= 84.6 minutes