He best ultraviolet observations are made with space telescopes because a. the sun blocks most ultraviolet light from distant stars. b. the earth's gravity reflects most ultraviolet light from distant stars. c. the earth's atmosphere absorbs most ultraviolet light. d. space telescopes are closer to distant galaxies.

Achemistry student weighs out 0.306 g of citric acid (h3c6h5o7), a triprotic acid, into a 250 ml volumetric flask and dilutes to the mark with distilled water. he plans to titrate the acid with 0.1000 m naoh solution. calculate the volume of naoh solution the student will need to add to reach the final equivalence point. be sure your answer has the correct number of significant digits.