From wich country is this Maths textbook (7) ? Now including solution

Textbook_7

This textbook is from Zimbabwe. Title: Mathematics Revision, Grade 7.

Authors: Cletus J. Ngwaru & Margaret N. Zunguze.

First published: 1994.

Note: there are some mistakes in the text. E.g. The ‘Shona’-angle seems to be less than 90 degrees.