Use a single digit times the power of 10 to estimate the number 0.00002468

In simplified exponential notation, the expression a^2•a^-3•a 1/a 0

Which sum or difference identity would you use to verify that cos (180° - ∅) = -cos ∅? a. sin (α -β) = sin α cos β – cos α sin β b. cos (α -β) = cos α cos β – sin α sin β c. cos (α -β) = cos α cos β + sin α sin β d. sin (α + β) = sin α cos β + cos α sin β

For what is the measure of the angle at the top of the shed? a. multiplication of areas b. squaring of areas c. addition of areas d. division of areas