Suppose the radius of a circle is 3 what is its circumference?

There is a line with slope 1/a going through the point (a, a²). find the equation of the line perpendicular to this line at this point. (don’t let this problem intimidate you! solve the problem as you would if i’d given you specific values. just use variables instead.)

How many grams must be adde to 970g to make 1 and a half kg

Anyone know these questions? i need ,.