P=2(l+w)
50=2(4+w)
50=8+2w
collect the like terms 50-8=2w
42=2w divide both sides by 2
w=21
If you already have 4% then that means that the other 48 grams is 96%.
So if you make a proportion with 96/100 and 48/x (x being a stand-in for the answer) you can cross multiply 48 and 100 and divide the end result by 96, which equals 50.
So that means that the answer is 50 grams of protein. Hope this helped!
For the graph in the figure
we know that
the function is a quadratic equation ( vertical parabola) open up
so
The vertex is a minimum
the vertex is the point 
The domain x of the function is all real numbers-------> (-∞,∞)
The range is the interval--------> [0,∞)

therefore
Statements
A) The range is the set of all real numbers
Is false
B) The domain is the set of all real numbers
Is true
C) The domain is the set of all real numbers greater than or equal to zero
Is false
D) The range is the set of all real numbers greater than or equal to zero
Is true