Which chemical equation below is balanced correctly?

al4c3 + > 3ch4 + 4al(oh)3
nacl + cao > na2o + cacl2
3lioh + fe(no3)3 > 2lino3 + fe(oh)3
zn + 2hcl > zncl2 + 2h2

A4.86 g piece of metal was placed in a graduated cylinder containing 15.5 ml of water. the water level rose to 17.3 ml. what is the density of the metal. i need the steps of how to solve it to so i can use a formula to work out other problems.

Pls ill give u brainliest which of the following is true about science? 1. political conditions are unable to influence it. 2. economic concerns may prevent it from solving problems.

Which words or phrases identify layers of groundwater? check all that apply. water table kettle lake saturation zone underground lake sinkhole will give brainiest, answer quickly.