Pedro is planning to model how changes in weather affect evaporation from lakes. For his first experiment, he wants to test how humidity affects the
evaporation rate. He places one beaker with 300 mL of water in a dry area,
and he places another beaker with 300 mL of water near a humidifier.
Which of the following variables does Pedro need to control during his
experiment?
O A. Volume of water only
B. Volume of water and temperature
C. Humidity and evaporation rate
D. Humidity only

Answerthe energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.explanationwe define electric potential as the ratio electric potential energy to the charge,    then the following gives us the potential difference,      the formula  may be on your formula sheet.the change in electric potential energy would be the energy that would needed to move it from point a to point b. solving for that, we get    using q = 8.00  × 10⁻¹⁹ c and  δv = 2.00 v, we get    the energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.

Newtons laws of motion

I'm very sorry if i'm wrong but i think it's a.

The answer is three because it just is