1- An investigation was carried out into the number of false negative results produced during COVID-19 testing. 95% of results were found to be accurate. 49 tests were found to be inaccurate. What was the sample size of the investigation?

2- To set up a chemical reaction, 20l of 20 mM reagent A was added to 50 l of water. 30l of 20 mM reagent B was also added. Calculate the concentration of both reagent A and B in the final reaction mix.

3- A laboratory manager was interested in buying a new pipette. Company A was selling 2 pipettes for 300 less than Company B was selling 3 pipettes for. For a single pipette, Company A was more expensive by 60 than Company B. What were the prices of Company A and B's pipettes

4-In a clinical trial, 3 patients were given different doses of the same drug. The first patient was give the recommended daily dose. The second patient was given 30 mg less than the first patient and the third patient was given half as much as the first patient. One vial containing 360 mg was enough to provide three rounds of doses for all three patients. Calculate the doses given to the first patient

5-An investigation was carried out to see if there was a relationship between the concentration of glucose given to cells and the growth rate of those cells. When then concentration of glucose was zero, the cells had a growth rate of 50 cells per hour. A concentration of 10 mM resulted in a growth rate of 100 cells per hour. A concentration of 30 mM resulted in a growth rate of 200 cells per hour. What an algebraic equation that demonstrates this relationship.

6-If a blood glucose level falls from 8.1 mmol/l to 4.2 mmol/l, what would be the percentage decrease to the nearest integeral