All of the following activities produce quantitative data exept
a. measuring the rate of gas production from a chemical.
b. describing the clarity of water in a sample
c. calculating the energy released from an electrochemical reaction

The answer to your question are A and C

Explanation:

Quantitative data are quantities, something that we get after measuring something.

A. Measuring the rate of gas production from a chemical.  This example is a quantitative measure, because we are measuring the rate.

B. Describing the clarity of water in a sample  If we are describing something, means that we are not measuring anything, so this is not a quantitative measure.

C. Calculating the energy released from an electrochemical reaction If we are not measuring but we are using the data somebody else got to calculate energy, them this is a quantitative data.