$(\,4+\,b)\;(\,6\,a+\,1) = $   ?

$\,24\,\,a +\,4 +\,6\,\,a\,b +\,\,b$ $\,10\,\,a +\,5 +\,7\,\,a\,b +\,2\,\,b$ $\,31\,\,a^2\,b^2 +\,4$ $\,6\,\,a\,b +\,4$

$(\,6\,y+\,6)\;(\,2\,y+\,3) = $   ?

$\,12\,\,y^2 +\,18$ $\,42\,\,y +\,18$ $\,12\,\,y^2 +\,30\,\,y +\,18$ $\,8\,\,y^2 +\,17\,\,y +\,9$

$(\,5+\,a)\;(\,4+\,b) = $   ?

$\,10\,\,a^2\,b^2 +\,20$ $\,9 +\,6\,\,b +\,5\,\,a +\,2\,\,a\,b$ $\,\,a\,b +\,20$ $\,20 +\,5\,\,b +\,4\,\,a +\,\,a\,b$

$(\,4+\,b)\;(\,2\,b+\,3) = $   ?

$\,2\,\,b^2 +\,11\,\,b +\,12$ $\,13\,\,b +\,12$ $\,2\,\,b^2 +\,12$ $\,3\,\,b^2 +\,10\,\,b +\,7$

$(\,x\,-6)\;(\,3+\,5\,y) = $   ?

$\,3\,\,x +\,5\,\,x\,y \,-18 \,-30\,\,y$ $\,-3\,\,x \,-5\,\,x\,y \,-18 \,-30\,\,y$ $\,3\,\,x \,-5\,\,x\,y \,-18 \,-30\,\,y$ $\,-3\,\,x +\,5\,\,x\,y +\,18 \,-30\,\,y$

$(\,4\,t+\,2)\;(\,-\,x\,-1) = $   ?

$\,4\,\,t\,x \,-4\,\,t +\,2\,\,x \,-2$ $\,-4\,\,t\,x +\,4\,\,t \,-2\,\,x \,-2$ $\,-4\,\,t\,x \,-4\,\,t \,-2\,\,x \,-2$ $\,4\,\,t\,x \,-4\,\,t \,-2\,\,x +\,2$

$(\,y\,-5)\;(\,3+\,4\,y) = $   ?

$\,4\,\,y^2 \,-17\,\,y \,-15$ $\,-4\,\,y^2 \,-17\,\,y +\,15$ $\,-4\,\,y^2 +\,23\,\,y \,-15$ $\,-4\,\,y^2 \,-23\,\,y \,-15$

$(\,5\,b\,-3)\;(\,-1\,-\,a) = $   ?

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

$(\,2\,y\,-6)\;(\,-\,y+\,4) = $   ?

$\,-2\,\,y^2 +\,14\,\,y \,-24$ $\,-2\,\,y^2 \,-2\,\,y \,-24$ $\,2\,\,y^2 +\,14\,\,y +\,24$ $\,-2\,\,y^2 +\,2\,\,y +\,24$

$(\,6\,-4\,a)\;(\,-1\,-2\,a) = $   ?

$\,8\,\,a^2 \,-8\,\,a \,-6$ $\,-8\,\,a^2 +\,16\,\,a \,-6$ $\,8\,\,a^2 +\,16\,\,a \,-6$ $\,8\,\,a^2 \,-16\,\,a \,-6$