Please help I beg you, I will pay too Do you think standardized testing to measure the effects of the pandemic is “unnecessary or even actively harmful” this year — or, do you think schools need to administer those tests to see where students stand

Simplify (a/b - b/a) times (a - a^2/a+b) a - a^2/a=b is a mixed number

Convert the mixed numbers into improper fractions. convert the improper fraction to mixed numbers.

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters