Tag: science & technology

Togo has a small remaining rainforest area of approximately 1,300 square kilometers. This is a factual geographical question about rainforest coverage in West African nations, where Togo has experienced significant deforestation but retains small forested areas.

Rainforests cover approximately 2% of the Earth's total surface area. This is a standard geographical fact - despite their ecological importance, tropical rainforests cover a small fraction of the planet's surface, roughly between 2-3% depending on classification criteria.

The frequency range of human speech typically spans from approximately 100 Hz to 7 kHz. This range captures the fundamental frequencies of adult voices (around 85-255 Hz for males, 165-255 Hz for females) plus the harmonics and formants that extend into the kHz range for intelligible speech.

The frequency range of human hearing is 20 Hz to 20 kHz for healthy young adults. This is the standard audiological range - below 20 Hz are infrasounds and above 20 kHz are ultrasounds that humans cannot perceive.

The frequency range used in traditional telephone systems is 300 Hz to 3.4 kHz. This is known as the 'voice band' or 'telephone bandwidth' - it was chosen to preserve intelligible speech while minimizing bandwidth requirements in early telephony infrastructure.

The bandwidth of a narrow band communication channel is 64 Kbps. This is a standard telecommunications specification - 64 Kbps (kilobits per second) is the bandwidth of a single digital voice channel, commonly used in ISDN and other telephony standards. The option '64KBps' would be incorrect as it refers to kilobytes.

SCRA (Special Class Railway Apprentices) is a UPSC-conducted examination for recruitment to the Indian Railways' mechanical engineering cadre. It's a highly competitive exam for mechanical engineers, not about railway authority or assistance.