Which expression is equal to 81÷3

Ac contractor is building a new subdivision outside of the city. he has started work on the first street and is planning on the other streets to run in a direction parallel to the first. the second street will pass through (-2,4) find the equation of the location of the second street in standard form. a.2x+y=2 b. x-y=2 c.2x+y=2 d.x+y=2

In the following situation, determine whether you are asked to determine the number of permutations or combinations. then do the calculation how many ways are there to pick a starting five from a basketball team of twelve members? a. permutation; ps - 2520 b. combination; 1c, - 792 c. combination: 2cs - 2520 d. permutation; ps - 95040

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?