2. Importance of root and tuber crops in Africa. In Africa, roots and tubers are generally grown in countries located in the Sub-Saharan zones, notably in Nigeria, Ghana, Cote cÃ´te'D, Ivoire, Nigeria, Benin, Cameroon Central African, Republic.D.R, C, Tanzania, Mozambique, Angola, Uganda, Malawi madagascar And. rwanda
The healthy human ear can hear frequencies ranging from 20Hz to 20,000 Hz. Over time, the hair cellâs hair-like stereocilia may get damaged or broken. If enough of them are damaged, hearing loss results. The high frequency area of the cochlea is often damaged by loud sound.
Just how loud are cicadas? Cicadas are among the loudest insects known to man, and a swarm of them can produce sounds up to 120 decibels. That's louder than a rock concert (about 115 decibels), and comparable to the noise from a chainsaw (humans start to experience pain from sound at the 110 to 120 decibel level).