A virus particle can be 400 manometers long. Express this number in scientific notation 4x10^-11 m

4x10^-9 m

4x10^-7 m

400x^10-9 m

50 ! pls ! 12.  building codes regulate the steepness of stairs. homes must have steps that are at least 13 inches wide for each 8 inches that they rise.

a. discuss how to find the slope of the stairs.
b. describe how changing the width or height affects the steepness of the stairs.

Rob spent 25%, percent more time on his research project than he had planned. he spent an extra h hours on the project. which of the following expressions could represent the number of hours rob actually spent on the project? two answers

Choose the more precise measurement. 26.4 cm or 8.39 cm