How do you solve 11=m-4 as a one step

1: 4 if the wew 35 surfboards at the beach how many were short boards?

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?

What’s the range cuz i can’t find it?