The local newspaper has letters to the editor from 40 people. If this number represents 5% of all the newspaper's readers, how many readers (r) does the newspaper have?
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Plz ( true - false) all triangles have interior angles whose measure sum to 90.

Hurry which expression is equivalent to 3√x^5y?

Which sum or difference identity would you use to verify that cos (180° - q) = -cos q? a.) sin (a -b) = sin a cos b – cos a sin b b.) cos (a -b) = cos a cos b – sin a sin b c.) cos (a -b) = cos a cosb + sin a sin b d.) sin (a + b) = sin a cos b + cos a sin b