4. Which of the following systems has an infinite number of solutions? A x+y=1 and x– y=1
B. x+y=1 and x +y=-1
C. x+y=1 and -x - y = -1
D. x+y=1 and x+ y= 2

Consider the function f(x)=−2/3x+5 . what is f(1/2) ? enter your answer, as a simplified fraction, in the box. f(1/2)=

Calculate the density of benzene if 300ml of it weighs 263g. a. 0.88 g/ml b. 1.14 g/ml c. 78,900 g/ml d. 37 g/ml

Frank owns a $141,000 home, for which he has a 30-year mortgage in the amount of $700 a month. once he has paid off mortgage, how much will he have paid in investment? a. $111,000 b. $109,000 c. $120,000 d. $141,000