求下列各數的值;;
a.(-10)(+7) = __
b.(+5)(-3) = __
c.(+2)(+13)(+4) = __
d.(-3)(-7)(-9) = __
e.(-3)(+12)(-5) =__
f.(+4)(+17)(-3) = __
g.(+144)除以(+12) = __
h.(-81)除以(-9) = __
i. (-169)除以(+13) = __
j. (+196)除以(-14) = __