Answer:1. Transparent
2. Transparent
3. Opaque
Explanation: In a transparent medium light can pass through. For opaque objects it does not allow to pass through instead it is reflected back.
The answer is C. You must divide your wavelength and your frequency to get your answer.
Explanation:
Efficiency is defined as the ratio between the useful output over the total amount consumed. 
The fan does 500W of useful work while wasting 300 W. The total power consumption is 800 W (500 + 300).
3.5m is ur answer ask for more questions anytime
I literally looked everywhere for the answer, and I still found nothing. I hope you get it right. Sorry.