Nacl es basico metal o acido no metal

The answer for #3 is c but i don't know why

Which is a chemical property of iron? a. it forms iron oxide (rust) when exposed to moisture and air. b. it is a gray–black metal that is hard to the touch. c. it has a melting point of 2795°f (1536°c). d. it is a good conductor of heat

What does the xylem do? stores the glucose captures the sunlight absorbs oxygen into the leaf carries water from the roots to the leaves