I don’t know what it is, help

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

Is powdered sports drink ionic or covalent ? 10pts !

He table below gives the atomic mass and relative abundance values for the three isotopes of element m. relative abundance (%) atomic mass (amu) 78.99 23.9850 10.00 24.9858 11.01 25.9826 what is the average atomic mass (in amu) of element m? 2.86 5.36 24.30 24.98