4) Conservation of energy means that a. energy can be created but not destroyed
b. energy can be destroyed but not created
c. energy can both be created and destroyed
d. energy can neither be created nor destroyed

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