1 The last big problem of the building has many problems.

1. A classmate found that the sum of the inner angles of a polygon was 1 125 when calculating the sum of the inner angles. When he found the mistake, he rechecked it and found that an inner corner was missing. What is the inner angle? What is the sum of the internal angles of several polygons?

The formula for calculating the sum of the degrees of the internal angles of a polygon is = 180n-360(n stands for the number of sides).

You can list inequalities.

180m-360 & lt； 1 125 & lt； 180n-360

soluble

m=8

n=9

This is a 9-sided shape.

This angle =180 * 9-360-1125 =135.

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How much is four plus eight?

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Third, complete the dialogue.

Children, can I help you?

Yes (to c) What do you want?

Well, I want to eat something. I like some bread. (What) (About) you?

I want two cakes. How about something to drink? I'd like a whisky.

Well, I want a cup of tea.

We want some bread, (some) cake, a cup (tea) and a cup (milk).

A: OK. Please wait a moment.

Yes, (thanks) (thanks c)