Energy consumption is a major challenge that faces the entire human population in the 21st century. Discuss one alternative energy source that you strongly believe in and explain why you feel this way.

In which situation has the independent variable for the experiment been changed? check all that apply. changed from counting the number of duckweed at day 0 and day 14 to counting them every day changed from testing duckweed growth in beakers to testing duckweed growth in large outdoor tanks changed from testing the effect of ph on duckweed growth to testing the effect of light levels on duckweed growth changed from testing the effect of acid ph on duckweed growth to testing the effect of basic ph on duckweed growth

Because light travels in a straight line and casts a shadow, isaac newton hypothesized that light is

The earth exerts a gravitational force of 500 n on amy. what is amy’s mass in kg?