How many numbers are 9 units from 0

One expression below in undefined, and the other expression has a well defined value. which expression is undefined and explain why it has no value. which expression is defined? what is the value of that expression and how do you know? what is a different expression using a trig inverse function that is also undefined?

Which expression is equivalent to (4x^3*y^5)(3x^5*y)^2 \a) 24x^13*y^7b) 36x^13*y^7c) 36x^28*y^7d) 144x^16*y^12

The weight v of an object on venus varies directly with its weight e on earth. a person weighing 120 lb on earth would weigh 106 lb on venus. how much would a person weighing 150 lb on earth weigh on venus?