It stopped in 11,700 years ago
Schizocoelic development
The coelom is a fluid-filled body cavity, where the internal organs are suspended in. It is the cavity between the wall of the body and the digestive tract.
In the schizocoelic development of the embryo, the coelom, called the schizocoel, develops as a split in the mesoderm. The outer layer of the mesoderm attaches with the ectoderm to form a body's musculature, while the inner layer attaches with the endoderm to form the wall of the digestive tract.
This type of development is commonly found in annelids, arthropods, and mollusks.
Crossing over happens in Meiosis 1 only. In Prophase 1 a cells chromatin (chromatin = chromosomes that have not condensed yet) condense and pair up forming homologous chromosomes (paired = XX (2 chromosomes together)). When this happens segments/ alleles of the chromosomes pairing up swap over. This creates genetic diversity as each chromosome is different, it has parts from its pair. This leaves every chromosome unique and individual.
I hope this helps, sorry some of the vocab is rather technical. By the way I would suggest watching the
'Crash Course: Meiosis' on YouTube, this really helped me when I was learning this topic. :D
C) because solar, wind, hydro, geothermal, biomass, ocean are all was thaer
Carbon dioxide and water are released as by-products. (A)