What is the mass of lead?

How is 0.00235 expressed in proper scientific notation? a. 2.35 × 10-3 b. 0.235 × 10-2 c. 2.35 d. 2.35 × 103

Calculate the frequency of a wave in a spring toy. the wave has a speed of 1.1 meters per second and a wavelength of 0.1 meters. *

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?