Answer the question and these wrong answers are bad

Problem page gaseous ethane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water . if of water is produced from the reaction of of ethane and of oxygen gas, calculate the percent yield of water. be sure your answer has the correct number of significant digits in it.

Solar energy is energy from the sun that is converted into thermal or energy. a. nuclear b. mechanical c. electrical d. chemical

What’s the scientific notation for the number 6,840,000,000