Calcium is essential to tree growth because it promotes the formation of wood and maintains cell walls. In1990, the concentration of calcium in precipitation in a certain area was 0.11 milligrams per liter(mg/L). A random sample of 10 precipitation dates in 2007 results in the following data table. Complete parts(a) through(c) below.

Date Table:

0.066, 0.076, 0.074, 0.256, 0.113, 0.185, 0.125, 0.213, 0.315, 0.099

Click the icon to view the data table.

(a) State the hypotheses for determining if the mean concentration of calcium precipitation has changed since 1990.

H0: _____ _____0.11 mg/L

H1: _____ ______0.11 mg/L

First set of options

p

Second set of options

less than

<

not equals

equals

=

greater than

>

(b) Construct a 95% confidence interval about the sample mean concentration of calcium precipitation.

The lower bound is ______

The upper bound is ______

(Round to four decimal places asneeded.)

(c) Does the sample evidence suggest that calcium concentrations have changed since1990?

A.

No, because the confidence interval doesnotcontain 0.11 mg/L.

B.

Yes, because the confidence interval contains 0.11 mg/L.

C.

No, because the confidence interval contains 0.11 mg/L.

D.

Yes, because the confidence interval doesnotcontain 0.11 mg/L.