What type of combustion is best described as solid fuel that is porous and charring on the surface?

All of the following describe the adaptive immune system except

a. Also known as the natural immune system b. Consists of antigen presenting cells c. Displays an anamnestic response d. Is involved in allograft rejection

________ is U.S. federal government health care assistance, enacted by each state, for indigent or low-income persons

Fill in the blank(s) with correct word