Exams

Helioseismology is the study of the solar interior using observations of waves on the Sun's surface. It has done much to improve our understanding of the interior of the Sun, testing the physical inputs used to model stellar interiors and providing a detailed map of the Sun's structure and internal rotation.

Internet service providers (ISP's) emerged in the late 1980's and early 1990's.

The ARPANET was decommissioned in 1990.

By 1995, the Internet was fully commercialized in the U.S., when the NSFNet was decommissioned, removing the last restrictions on use of the Internet to carry commercial traffic.

Benjamin Franklin has long been credited with the invention of bifocal lenses and he was the first to wear bifocal lenses. He did not produce them himself but instead had some optician in London or France make them for him to overcome Presbyopia, a condition that Franklin suffered. He was tired switching between lenses for far and near sightedness. And that resulted in inventing Bifocal Lenses.

Mass of zinc ore = 8000 kg

Mass of metal = 60% of 8000 = 4800 kg

Mass of silver in metal = 3/4 x 4800/100 = 36 kg

Mass of zinc = 4800 - 36 = 4764 kg.

Perimeter of the rectangle is given by 3000/10 = 300 mts

But we know,

The Perimeter of the rectangle = 2(l + b)

Now,

2(8x + 7x) = 300

30x = 300

x = 10

Required, Area of rectangle = 8x x 7x = 56 x 100 = 5600 sq. mts.