Plz help the question is in the pic

Which expression is equivalent to 2^4y^3

Arefrigeration system at your company uses temperature sensors fixed to read celsius (°c) values, but the system operators in your control room understand only the fahrenheit scale. you have been asked to make a fahrenheit (°f) label for the high temperature alarm, which is set to ring whenever the system temperature rises above –10°c. what fahrenheit value should you write on the label

Valentina is subtracting from . she finds the lcd to be 15y2. what is valentina's next step?