What is square root of 81

What is an estimate of the value of 0.0000000055 as a product of a single digit and a power of 10?

Sanda has 16 red roses and 40 white roses she wants to make arrangements with the same amount to red roses and white roses. how many arrangements can she make

The measures of two supplementary angles have a ratio of 2:4. What is the measure of the smaller angle?

5 4/5 b+6 3/4 - (2 11/15 + 7 7/12)

A circle has a diameter of 10 cm. What is the best approximation of its area? Use 3.14 to approximate for π.

A newspaper reporter wants to know how popular the hobby of bird watching is in the city. He asked people at the local bird refuge if they watched birds as a hobby. Which of the following best explains whether the reporters data is valid or not?

I am very confused on how to figure out if y = 3/4x is proportional?

Alison wants to buy a mountain bike for $339.12. If she saves $28.26 each month, in how many months will she be able to buy the bike?

At 12 o'clock the temperature was 7°C. The temperature decreased by - 20°C. What is the new temperature?

Ashleys rentals charges $27.50 per hour to rent a surfboard and a wetsuit. Darlas surf shop charges $23.25 per hour to rent a surfboard plus $17 extra for a wetsuit.