What is 23.7x3.82 the appropriate number of significant figures

Long term exposure to waves can cause sunburns and skin cancer. a) visible b) infrared c) gamma rays d) ultraviole

Is a pencil falling to the floor anon contact force, a force, or a contact force

Using the first volume and temperature reading on the table as v1 and t1, solve for the unknown values in the table below. remember to use the rules of significant figures when entering your numeric response.