Answer:
(a) The angular frequency ($\omega$) of a spring/mass system with a force constant ($k$) and a mass ($m$) can be found using the formula:
\omega = \sqrt{\frac{k}{m}}
Plugging in the values given, we get:
\omega = \sqrt{\frac{90 N/m}{8.15 kg}} \approx 3.18 \text{ rad/s}
Therefore, the angular frequency of the spring/mass system is approximately 3.18 rad/s.
(b) The period ($T$) of a spring/mass system can be found using the formula:
T = \frac{2\pi}{\omega}
Plugging in the value of $\omega$ we found in part (a), we get:
T = \frac{2\pi}{3.18\text{ rad/s}} \approx 1.98 \text{ s}
Therefore, the period of the spring/mass system is approximately 1.98 s.