What was the pressure in discharge used for discovery of cathode rays: or or ​

Asample of air with a volume of 2.20m3 at a pressure of 105 kpa and a temperature of 30c is cooled to 10c and the pressure is reduced to 75.0 kpa. what is the new volume? 6.9 1.34 2.56 43.0 2.88

How many moles is 14.5 cm^3 of platinum? the density of platinum is 21.45 g/cm^3.

Scientists have developed an explanation of a phenomenon from several verified hypotheses. the explanation has been confirmed through numerous experimental tests.which option best describes this explanation? a. scientific lawb. research questionc. hypothesisd. scientific theory