Close to 28 million tons of rubber were produced in 2013, of which approximately 44% was natural. Since the bulk is synthetic, which is derived from petroleum, the price of natural rubber is determined, to a large extent, by the prevailing global price of crude oil.    Asia was the main source of natural rubber, accounting for about 94% of output in 2005. The three largest producers, Thailand , Indonesia ( million tons)  and Malaysia, together account for around 72% of all natural rubber production. Natural rubber is not cultivated widely in its native continent of South America due to the existence of South American leaf blight , and other natural predators.
Push-ups can work to build your muscles, increasing your breast size . Get into the push-up position with your hands placed shoulder width apart. Be sure that your body remains straight and don’t relax the hips. Lower your body slowly, until your face is almost touching the ground. Use your arms to push yourself back to the starting position. Try to do three reps of eight. If you aren’t able to do traditional push-ups, try doing the modified version. To do the modified version, rest your knees on the ground. Bend the elbows to lower your chest toward the ground. Do three reps of ten.