this is a direct current circuit.
Answer:
A. 
B. 
Explanation:
The frequency has an inversely proportional relationship with the concept of wavelength, the greater the wavelength, the lower the frequency. For electromagnetic waves, the frequency is equal to the speed of light, divided by the wavelength.

A.

B.

Put vinegar in a water bottle with no water, fill a balloon with baking soda, without pouring the baking soda in the vinegar put the balloon on the water bottle, then lift it so the baking soda goes in the vinegar, this will blow up the balloon