Questions

The nearest stars to Earth are in the Alpha Centauri triple-star system, about 4.37 light-years away. One of these stars, Proxima Centauri, is slightly closer, at 4.26 light-years.

Of all the stars closer than 15 light-years, only two are spectral type G, similar to our sun: Alpha Centauri A and Tau Ceti. The majority are M-type red dwarf stars.

Only nine of the stars in this area is bright enough to be seen by the naked human eye from Earth. These brightest stars include Alpha Centauri A and B, Sirius A, Epsilon Eridani, Procyon, 61 Cygni A and B, Epsilon Indi A and Tau Ceti.

the powerful cell phones can transmit a signal of 3 watts.

In a brief, the system software is the interface between the hardware and user applications. System software is a type of computer program that is designed to run a computer’s hardware and application programs.

Examples : OS, System utilities, BIOS like mouse, keyboard, hard disc, Device drivers, Assembler,...