How are beef and gas productions related to methane levels?

Plzzz answer quick

Idon’t know how to solve this question

Which class of molecules functions as chemical signals? hormones water carbohydrates proteins

Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium