Gases that contribute to the greenhouse effect include: 1  Water vapor. 2  Carbon dioxide (CO 2). 3  Methane. 4  Nitrous oxide. 5  Chlorofluorocarbons (CFCs).
You can start maternity leave any time from 11 weeks before the beginning of the week your baby's due. You can bring the date forward if you need to take time off work for pregnancy-related reasons within four weeks of the expected birth date. Your employer may make you start your leave from then.
sondie24. You can't take sick leave until you are atleast 25 weeks pregnant and would need a dr. note. Otherwise, you can't go on maternity leave until you are 32 weeks pregant. They also do not have to approve the sick leave, I was taken off work early and they denied me. You can go off work any time you want to but it will not be paid until these minimums are met and you have enough hours worked to qualify.