Who invented Phillips rechargeable led bulb​

What color of light must blue light mix with to create white light? a. yellow b. white c. blue d. green

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?

The average density of the planet uranus is 1.27 103 kg/m3. the ratio of the mass of neptune to that of uranus is 1.19. the ratio of the radius of neptune to that of uranus is 0.969. find the average density of neptune.