Read the elapsed time on the stopwatch and answer the questions. In which digit is there the least amount of confidence?
How many significant figures does this measurement have? I need help quick

You are sitting on the beach and wondering about the properties of mechanical waves. describe them in terms of ocean waves.

Suppose you use a machine that gives you a mechanical advantage of 2 to achieve an output force of 30newtons what must the input force be

Achemistry student needs of 40ml diethylamine for an experiment. by consulting the crc handbook of chemistry and physics, the student discovers that the density of diethylamine is 0.7 . calculate the mass of diethylamine the student should weigh out. round your answer to significant digits.