I think the answer is b as in boy.
Answer:
5.1 billion metric tons of carbon is emitted by U.S as compared to other countries which emits about 32.5 billion metric tons of carbon.
Explanation:
U.S emits about 5.1 billion metric tons of carbon in the atmosphere which contribute in air pollution also helps in rising the temperature of the earth atmosphere because carbondioxide is a green house gas which increases the earth temperature. The main reason of high amount of carbon emission is the high number of industries and more fossil fuels is burnt in the engines of vehicles.
I think what happens is that the Cyclin component of the MPF is degraded. MPF or mitosis promoting factor, consists of two important cell cycle regulatory protein called the cyclin and cyclin dependent kinases (CDK). The cdk and the cyclins are the major control switches for the cell cycle, causing the cell to move from G1 to S or G2 to M.
"Answer DThe outermost layer of old epidermal cells are sloughed off and replaced every 15 to 30 days. The sebaceous glands secrete sebum which maintains the skin pH between 3 and 5. Bacteria which metabolize sebum live as opportunistic pathogens on the skin and cause skin infections."