Question

1. in the code of federal regulations reference: 40 cfr 141.24, ______ is the only contaminant that has been shown to cause cancer for which standards have been set.

a. arsenic
b. chromium
c. radioactivity
d. thms

1. which of the following contaminants can potentially cause mental deficiencies primarily in children, if found in drinking water above the maximum level allowed by safe drinking water act?

a. copper
b. arsenic
c. mercury
d. lead

Explanation:

For question 9: 40 CFR 141.24 (drinking water standards) identifies arsenic as the only carcinogenic contaminant with established standards among the options.
For question 10: Lead exposure in drinking water above regulatory limits is well-documented to cause mental deficiencies, particularly in children, under the Safe Drinking Water Act.

Answer:

1. a. Arsenic
2. d. Lead