I dont get this please someone help

Afunction, f(x), represents the height of a plant x months after being planted. students measure and record the height on a monthly basis. select the appropriate domain for this situation. a. the set of all positive real numbers b. the set of all integers oc. the set of all positive integers od. the set of all real numbers reset next

Evaluate each expression. determine if the final simplified form of the expression is positive or negative -42 (-4)2 42

Is a triangle with sides of length 6ft, 21 ft, 23 ft. a right triangle?