Rayna is building a tapered staircase using bricks. The bottom stair is 45 bricks wide, and the top stair is 15 bricks ft wide. Each stair is 2
bricks shorter than the one below. What is the total amount of bricks
Rayna needs to build the staircase? Type the total amount of bricks.

The average human heart beats 1.15 \cdot 10^51.15⋅10 5 1, point, 15, dot, 10, start superscript, 5, end superscript times per day. there are 3.65 \cdot 10^23.65⋅10 2 3, point, 65, dot, 10, start superscript, 2, end superscript days in one year. how many times does the heart beat in one year? write your answer in scientific notation, and round to one decimal place.

If you can solve all of these i will give ! - 4% of 190 - 4% of 162.5 - 4% of 140 - a 4% increase from 155.1 - a 4% increase from 159.8

Drag the tiles to the correct boxes to complete the pairs. using the properties of integer exponents, match each expression with the correct equivalent expression.