1. Physical Weathering. In physical weathering the rocks are broken down into smaller pieces, but the chemical composition of the rock remains the same. Temperature Change. Hot temperatures can give rise to thermal expansion in rocks and cool temperatures can cause rocks to contract.
Buffett Donates $2.8 Billion, Breaks Personal Giving Record. Warren Buffett has bested his own personal philanthropy record once again, donating $2.8 billion to the Bill and Melinda Gates Foundation and several other charities as part of his annual giving pledge. The gifts given Monday top last yearâs $2.6 billion donation.
The north office building of the newly opened $500m Bill and Melinda Gates Foundation campus in  Seattle, Washington, US. The Gates Foundation supports work in more than 100 countries in areas of health, development, and education. Photograph: Marcus Donner /Reuters The story of the worldâs largest private foundation begins with a couple reading a news article about suffering in the developing world.