(5-(-4)^2)^2 This is Order of Operations with Signed Numbers. I have algebra 1. This is very confusing and if someone could provide the steps to do PEMDAS, that would be good too :)

Atriangle has a side lengths of 18cm, 80 cm and 81cm. classify it as acute obtuse or right?

The radius of a sphere is 3 inches. which represents the volume of the sphere?

Abicycle training wheel has a radius of 3 inches. the bicycle wheel has a radius of 10 inches.approximately how much smaller, in square inches and rounded to the nearest hundredth, is the area of the training wheel than the area of the regular wheel? *