What is the answer for A, B, C? Please answer fast

Liz is shipping a package to her friend.the maximum weight of a medium flat-rate box is 20 pounds,including the box which weighs 6 ounces.write and solve an inequality to describe the possible weight ,w, of the contents that liz will ship to her friend if she must use a medium flat-rate box.

In the equation sqrt(n+5)-sqrt(11-10)=1. what is the value of n

The graph represents f(x)=[x]+3. what is f(-2.2)?