Answer
a., b., and e
Work Step by Step
a. A wedding ring is probably an alloy, which has a uniform texture and composition, so it is a homogeneous mixture.
b. Sweat has a uniform texture and composition, so it is a homogeneous mixture.
c. Nile River water is a heterogeneous mixture because it does not look uniform; there are substances that may be present in larger amounts in different areas of the river.
d. Human blood is a heterogeneous mixture because its composition is not uniform. There are different amounts of substances in blood that are not in uniform proportions.
e. Compressed air in a scuba tank is composed of a homogeneous mixture of air.
