Radioactive element ‘A’ decays over time to element ‘B’. Element ‘A’ has a half-life span of 5 days. If you started with 20 grams of A and 0 grams of B, how many grams of B would there be after a total of 10 days? 1) 0 grams

2) 2.5 grams

3) 5 grams

4) 7.5 grams

5) 10 grams

6) 12.5 grams

7) 15 grams

8) 17.5 grams

9) 20 grams

10) 22.5 grams

11) 25 grams

12) 27.5 grams

Match the digestive enzymes to the macromolecules they to digest. break down fats into glycerol and fatty acids break down carbohydrates into simple sugars break down nucleic acids into nitrogenous bases and simple sugars break down proteins into amino acids

The phlogiston theory in the 17th century attempted to explain burning. the theory stated that combustable objects contained a material called phlogiston, a substance without mass, color, odor, etc. after objects burned, the objects were dephlogistonated and were then in their true form. the phlogiston theory was accepted until the 18th century, when lavoisier proved that combustion requires a gas that has mass. phlogiston is considered a) to be scientific knowledge b) not to be scientific knowledge c) to be proven by scientific method d) to be accepted in the modern scientific community

Ausable water source is one that can be used by humans for drinking or agriculture. identify the water reservoirs as usable or unusable based on their current state. oceans rivers glaciers freshwater lakes groundwater