Proofs-of-concept are essential for validating new ideas.

I love collecting pull-off caps from different soda bottles.

The radii of curvature of the lenses determine the focal length of the camera.

The rat printing offices are located in the basement.

The rates of climb for these aircraft are impressive.

The rates of exchange are constantly fluctuating.

The rates of speed on the highway vary depending on the time of day.

The rate of climb indicators on the aircraft are not functioning properly.

The rate-of-climb indicators in the cockpit provide crucial information to the pilot.

There are many register offices in the city.