What scientific instrument is sensitive enough to detect a planet transiting a star?

Achemistry student needs to standardize a fresh solution of sodium hydroxide. he carefully weighs out of oxalic acid , a diprotic acid that can be purchased inexpensively in high purity, and dissolves it in of distilled water. the student then titrates the oxalic acid solution with his sodium hydroxide solution. when the titration reaches the equivalence point, the student finds he has used of sodium hydroxide solution.calculate the molarity of the student's sodium hydroxide solution. be sure your answer has the correct number of significant digits.

About 3% of the water on earth is freshest. only about 40% of that freshwater is available for human use. why is so much freshwater unavailable for human use?

If many scientists conduct the same or similar experiments, and all obtain similar results, a can be written, which is a generally agreed-upon statement that explains and predicts how a natural phenomenon works.