Which reaction is a combustion?

a. fe + s8 → fes
b. h2o → h2 + o2
c. zn + hcl → zncl2 + h2
d. nacl + agno3 → nano3 + agcl
e. hbr + naoh → nabr + h2o
f. c10h8 + 12 o2 → 10 co2 + 4 h2o

The act of moving from one place to another. a. locomotor b. aerobic c. stationary d. static

The current in a hair dryer measures 11 amps. the resistance of the hair dryer is 12 ohms. what is the voltage?unit:

Because air contracts as it cools, the air pressure inside a freezer is typically lower than on the outside. why do ice cubes inside a freezer tend to shrink over time? a. the ice dissolves oxygen from the air, forming a denser crystalline matrix.b. the ice reacts chemically with carbon dioxide in the air, forming gaseous carbon compounds.c. the ice melts, and then the liquid freezes as ice crystals on the bottom of the freezer.d. the ice sublimes, and then the water vapor deposits as ice crystals on the sides of the freezer.