Of the chemicals that fall under the toxic substances control act, % have been thoroughly tested for toxicity and have been tested for endocrine, nervous, or immune system damage.

10 percent and for the second blank the answer should be none 

That is true tge cactus as a structural adaptation to its envirinment has it leaves reduced to spines. but this doesnt mean it cant produce food it produces food because of the presence of chlorophyll in its stem