Why does the graph through the point (0,0)

How many absorptions would you expect to observe in the 13c nmr spectra of the following molecules? a) 3-chloropentane b) cis-4-methyl-2-pentene

A4.86 g piece of metal was placed in a graduated cylinder containing 15.5 ml of water. the water level rose to 17.3 ml. what is the density of the metal. i need the steps of how to solve it to so i can use a formula to work out other problems.

Fill in the blanks for the following statements: the rms speed of the molecules in a sample of h2 gas at 300 k will be times larger than the rms speed of o2 molecules at the same temperature, and the ratio µrms (h2) / µrms (o2) with increasing temperature. a not enough information is given to answer this question b sixteen, will not change c four, will not change d four, will increase e sixteen, will decrease