Help please:) A protist can be an autotroph, hetertroph, or potentially both. how is an autotroph different from a heterotroph?

Consider the point on the plot where 10.0 g of naoh have been added. what amount of naoh, in moles, has been added? 0.308 mol fecl3 initially present

Iknow #2 is d. i just need to know why

Butadiene undergoes a reaction at a certain temperature in the gas phase as follows: 2c4h6(g) --> c8h12(g) the following data were collected for this reaction: time (min) [c4h6] (m) 0 0.36 15 0.30 30 0.25 48 0.19 75 0. determine the order of the reaction and the rate constant. 1st order and k = 4.3x10 -4 s-1 1st order and k = 2.3x10-4 s-1 2nd order and k = 4.3x10-4 s-1 2nd order and k = 2.3x10-4 s-1 zero and k = 4.3x10-4 s-1