9. Substances are classified as metals and non-metals. Gold pure substance. Explain and describe why gold is classified as a pure substance. You may use diagrams in your explanation.

Given that ot =5, xt=12, and ox= 13 is xy tangent to circle o at t? explain.

Marla bought a book for $12.95, a binder for $3.49, and a backpack for $44.99. the sales tax rate is 6%. find the amount of tax and the total she paid for these items

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.