Africa has been called the “dark continent” for a long time because ____ lacks technology, electricity and other ____ (achieve) of the modem world. However, it is beginning to change. Africa is starting to catch up with ____ (industry) countries and the driving force behind this new development is the Internet and the World Wide Web.

    Now Africa is the fastest ____ (grow) place on the earth. So far, governments, businesses and individuals ____ (realize) that in order to develop quickly, modem technology is needed.

    Only ten years ago a SIM card used to cost about $100 in Niger. Today you can buy one for under $2 and phone calls have become much ____ (cheap), too. As a result, 23% of its population are now mobile phone users.____ (equip) with this new service, people can connect to the Internet easily. Many Nigerians have access ____ the World Wide Web now.

    In Ethiopia farmers can now get the prices of their farming products in real time. Until recently, most of the small farmers of the country did not know ____ the prices of their products were at ____ certain time. Today, they can phone in and get an up-to-the-minute report on prices.

俗话说“你不理财，财不理你。”李某在多年的投资中总结出一条非常重要的理财经验：“理财方程式＝50％稳守＋25％稳攻＋25％强攻。”这一理财公式的合理之处在于（    ）

下列不属于热力环流实例的是（　　）