Melanie spent four hours babysitting. she charges $16 upfront and then an additional charge per hour. the total amount she earned can be represented by
the expression $4x + $16. what expression represents the amount she earns each hour?

Tracy solved the following problem. which of the statements is true? 9 ÷ 3 + 6 × 2 3 + 6 × 2 9 × 2 18 her answer is correct. her answer is incorrect. she should have multiplied before dividing. her answer is incorrect. she should have multiplied before adding. her answer is incorrect. she should have added before dividing.

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle