C - concentration: 3.0M
n - number of moles: 1.50 moles
V - volume: ???
____________
C = n/V
V = n/C
V = 1.5/3
V = 0,5 L = 500 mL
:)
Answer:
It lies in in the <u>visible</u><u> </u><u>region</u><u>.</u>
Frequency: <u>is</u><u> </u><u>7</u><u>.</u><u>4</u><u>0</u><u>7</u><u> </u><u>×</u><u> </u><u>1</u><u>0</u><u>^</u><u>-</u><u>1</u><u>4</u><u> </u><u>Hz</u>

Explanation:
V is speed of light.
f is frequency
lambda is the wavelength
C ( Porcupines use there’s sharp quills to defend themselves from larger predators!)