Answer:
1 A systems <em>consultant</em> is an IT expert who looks at needs and designs software.
2 To solve the problem you need a clear, logical, <em>analytical</em>, approach.
3 My colleague's not very<em> communicative</em>. He rarely talks to the rest of us.
4 Modern forms of <em>communication</em> make it very easy to stay in touch.
5 With the fall in turnover this year, we need to find<em> </em>ways to <em>economize </em>next year.
6 There are a group of developers who are interested in buying the land and building new houses on it.
7 An outside agency has prepared an <em>analytical</em> document to suggest solutions to our current communication problems.
8 The charity Mercy Ships often uses <em>consultants</em> like Dr. Arras, who specialize in trauma surgery.
9 Most <em>economists</em> don't seem very optimistic about this recession ending anytime soon.
10 Recent <em>developments</em> in broadband speeds have made online meetings the norm.
Explanation:
To find the proper base words that will fit into the sentences, it is very important to examine the context of these sentences. For example, when matters relating to the economy are discussed as in the case of the fifth and ninth sentences, then the right base word should be "economy".
Also, when matters relating to specialization in a field are discussed, as in the case of the first and eight sentences, the right base word will be "consult". A consultant is an expert in a field who gives professional advice. A specialist in a medical field is also a consultant so this fits into the contexts of the first and eight sentences.