What are the dependent variables of the pond experiment

Anton created a chart listing different types of materials. which best complete the chart?

You are working in the lab and are working with the same element but with varying isotopes of the element. you are working with c-11, c-13, c-14, and c-15. what is the average atomic mass of this element? (use periodic table) a- 12 b-15 c-14 d-13

What type of plant is good for a bioassay and where can i buy it? i only have a month.