Which property do metalloids share with nonmetals?

Calculate the expected ph values of the buffer systems from the experiments (a,b,c,d), using the henderson- hasselbalch equation, ph-pka+log[a-]/[ha]. use for pka values carbonic acid= 6.37, and acetic acid= 4.75.

Can someone me with 3 and 4 plz. this is for masteries test.

Describe at least two advantages and two disadvantages of using hydropower as a source of energy.