(1) Northeast trade wind, equatorial low pressure zone

(2) The length and height of the dam are large, and the amount of work is large; the submerged land is large, and the amount of (relocation) immigrants is large; industry The foundation is weak and building materials and equipment need to be imported; the transportation is backward and transportation is inconvenient

,2,

Read the materials and complete the following questions.

Material 1 Figure 1 is a map of local areas in Africa. Figure 2 shows the precipitation statistics of cities A and B in Figure 1.

Material 2 Sudan has a weak industrial base and backward transportation and other infrastructure. Merowe Dam is 65 meters high and 9.7 kilometers long. It is the longest dam in the world, with a total investment of US$1.6 billion to US$1.8 billion. The Suder area is full of swamps, and the local people are mainly nomadic. In the 1980s, Sudan built the Jonglei Canal with a total length of 360 kilometers.

(1) Since city A is mainly affected by ( ) (the name of the air pressure zone or wind belt),

City B is mainly affected by ( ) (the name of the air pressure zone or wind zone) The impact results in a large difference in precipitation between cities A and B.

(2) Briefly analyze the reasons for the huge total investment in the construction of Merowe Dam.