Can someone help me with this one please I need help I will mark brainless

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?

Which of the following is a measure of the amount of light a star directly emits?               a.  luminosity    b.  intensity    c.  wavelength    d.  brightness

The brightest star in the night sky in the northern hemisphere is sirius. its distance from earth is estimated to be 8.7 light years. a light year is the distance light travels in one year. light travels at a speed of 3.00 × 108 m/s. calculate the distance from earth to sirius in miles. (1 mi = 5280 ft) g