$(\,4\,x+\,4)\;(\,1+\,5\,y) = $   ?

$\,20\,\,x\,y +\,4$ $\,44\,\,x^2\,y^2 +\,4$ $\,5\,\,x +\,9\,\,x\,y +\,5 +\,9\,\,y$ $\,4\,\,x +\,20\,\,x\,y +\,4 +\,20\,\,y$

$(\,3+\,5\,t)\;(\,4+\,6\,t) = $   ?

$\,68\,\,t +\,12$ $\,11\,\,t^2 +\,18\,\,t +\,7$ $\,30\,\,t^2 +\,12$ $\,30\,\,t^2 +\,38\,\,t +\,12$

$(\,1+\,a)\;(\,5+\,b) = $   ?

$\,5 +\,\,b +\,5\,\,a +\,\,a\,b$ $\,6 +\,2\,\,b +\,6\,\,a +\,2\,\,a\,b$ $\,7\,\,a^2\,b^2 +\,5$ $\,\,a\,b +\,5$

$(\,3+\,5\,b)\;(\,5+\,6\,b) = $   ?

$\,30\,\,b^2 +\,15$ $\,30\,\,b^2 +\,43\,\,b +\,15$ $\,11\,\,b^2 +\,19\,\,b +\,8$ $\,73\,\,b +\,15$

$(\,b+\,4)\;(\,a\,-3) = $   ?

$\,-\,\,a\,b +\,3\,\,b +\,4\,\,a \,-12$ $\,\,a\,b \,-3\,\,b \,-4\,\,a +\,12$ $\,\,a\,b \,-3\,\,b +\,4\,\,a +\,12$ $\,\,a\,b \,-3\,\,b +\,4\,\,a \,-12$

$(\,5\,-3\,a)\;(\,1\,-\,b) = $   ?

$\,5 +\,5\,\,b \,-3\,\,a \,-3\,\,a\,b$ $\,-5 \,-5\,\,b \,-3\,\,a +\,3\,\,a\,b$ $\,5 \,-5\,\,b +\,3\,\,a \,-3\,\,a\,b$ $\,5 \,-5\,\,b \,-3\,\,a +\,3\,\,a\,b$

$(\,1+\,6\,y)\;(\,-6+\,y) = $   ?

$\,6\,\,y^2 \,-37\,\,y \,-6$ $\,6\,\,y^2 \,-35\,\,y \,-6$ $\,6\,\,y^2 \,-37\,\,y +\,6$ $\,6\,\,y^2 +\,37\,\,y \,-6$

$(\,b\,-6)\;(\,-4\,-\,a) = $   ?

$\,4\,\,b \,-\,\,a\,b +\,24 +\,6\,\,a$ $\,-4\,\,b \,-\,\,a\,b +\,24 \,-6\,\,a$ $\,-4\,\,b \,-\,\,a\,b +\,24 +\,6\,\,a$ $\,-4\,\,b +\,\,a\,b +\,24 +\,6\,\,a$

$(\,3\,y\,-6)\;(\,y\,-4) = $   ?

$\,3\,\,y^2 \,-18\,\,y +\,24$ $\,-3\,\,y^2 \,-18\,\,y \,-24$ $\,-3\,\,y^2 +\,6\,\,y +\,24$ $\,3\,\,y^2 \,-6\,\,y +\,24$

$(\,x\,-2)\;(\,-3\,x\,-5) = $   ?

$\,-3\,\,x^2 +\,11\,\,x +\,10$ $\,-3\,\,x^2 +\,\,x +\,10$ $\,3\,\,x^2 +\,\,x \,-10$ $\,-3\,\,x^2 \,-\,\,x +\,10$