HELP ME with those questions please

Which of the following represents the ester functional group? a. -coo- b. -cho c. -cooh d. c=o

What is the area in square meters of 448 g ai foil that has a thickness of 23921 nm? the density is 2.70 g/cm

Which statement best identifies the process shown? the process must be fusion because energy is released. a.the process must be fusion because a heavier nucleus forms from smaller nuclei. b.the process must be fission because a large nucleus breaks into smaller nuclei. c.the process must be fission because neutrons are formed.